Since this discussion seems to be taking a turn in the direction of a civilized argument between advocates of high magnification versus advocates of wide fields of view, and since I have (not altogether without reason) been cast in the camp of high-power advocates, I'd like to comment a bit.
I cannot speak for Henry, of course, but what I have been hoping for all these years is to have eyepieces that serve us everything the scope they are attached to can deliver. That is, ideally, we should have a zoom eyepiece that, at the lowest magnification, offers all the field of view the telescope objective-prism system images, and then retains as much as possible of that field of view up to a top magnification high enough to show my eye all the detail the objective is capable of resolving.
For a scope such as the Swarovski 80mm, that would be a zoom that started with a field of 3.44 degrees at 20x and extended all the way up to 80x or more, with the subjective field of view gradually rising from the initial 69 degrees to 75-80 degrees at the higher magnifications, while the eye-relief remained comfortable and edge sharpness as good as the scope itself allows.
Since it seems that such a zoom eyepiece cannot yet be produced, at least not in an acceptable size-and-price range, I think the next best solution is to have two zoom eyepieces on offer, and that is what Swarovski and Leica are now moving towards. The 25-50x Wide is a good start, but alongside the current 20-60x zoom there is too much overlap in the specs for the two eyepieces to really complement one another.
So, in this real world, I'd like to see a manufacturer offering something like a 20-45x Wide zoom AND a 30-90x (as wide as possible) zoom. This would allow me to use the scope to its maximum under all conditions, although having to switch eyepieces now and then would still be an issue.
The other alternative would be the booster solution that Ilkka advocates, and that might actually work very well if the booster were of high enough quality and specifically designed for the purpose. Like Ilkka, I use a Zeiss 3x Classic monocular as a booster, and this would bring the range 75-150x into play with the upcoming zooms. The problems with this setup are first of all the magnification, which should be 2x (giving 50-100x) for the booster for this particular purpose, secondly the loss of light transmission and contrast that come from the addition of quite a number of air-to-glass surfaces, which in the Zeiss aren't even fully multicoated, and thirdly the very narrow field of view that the booster has. I'm sure that a much better dedicated telescope booster could be designed, but I'm less convinced that it would be a better solution than having two zoom eyepieces that would be designed to complement each other.
As far as practical preferences in the field, I will readily admit that I like high powers. I also like wide field, but when forced to choose between the two, and having a scope that takes magnification very well, I choose power. I don't know if I'm just lucky, but I rather frequently find myself using and benefiting from powers in the 50+, 60+ and even 70+ range. For example, just a week or so ago I was in a bird tower around noon, looking at sandpipers on mudflats, and although there was some heat haze in the air I was still benefiting from magnifications around 50x. When a cloud covered the sun, the air stabilized surprisingly quickly, and I soon found myself up at over 70x with perfectly clear and fine images. I find myself unwilling to give up this flexibility with magnification, although I would very much like to have wider fields as well. In the past, I have owned the (then) full range of wide-angle eyepieces for my previous Fieldscope and still have the 38x Wide, but have not used it much on the current scope. But, this is just me, and I understand Ilkka's preference as well and am definitely happy that two zooms that suit it are finally coming out.
As a last comment, limiting the magnification of the zoom to 50x also means that quality issues in the scope itself are not as easy to see. I don't think this is the reason why these zooms are limited to 50x, but when buying such a scope its good to keep in mind if one intends to later use the scope at higher magnifications.
Kimmo
I cannot speak for Henry, of course, but what I have been hoping for all these years is to have eyepieces that serve us everything the scope they are attached to can deliver. That is, ideally, we should have a zoom eyepiece that, at the lowest magnification, offers all the field of view the telescope objective-prism system images, and then retains as much as possible of that field of view up to a top magnification high enough to show my eye all the detail the objective is capable of resolving.
For a scope such as the Swarovski 80mm, that would be a zoom that started with a field of 3.44 degrees at 20x and extended all the way up to 80x or more, with the subjective field of view gradually rising from the initial 69 degrees to 75-80 degrees at the higher magnifications, while the eye-relief remained comfortable and edge sharpness as good as the scope itself allows.
Since it seems that such a zoom eyepiece cannot yet be produced, at least not in an acceptable size-and-price range, I think the next best solution is to have two zoom eyepieces on offer, and that is what Swarovski and Leica are now moving towards. The 25-50x Wide is a good start, but alongside the current 20-60x zoom there is too much overlap in the specs for the two eyepieces to really complement one another.
So, in this real world, I'd like to see a manufacturer offering something like a 20-45x Wide zoom AND a 30-90x (as wide as possible) zoom. This would allow me to use the scope to its maximum under all conditions, although having to switch eyepieces now and then would still be an issue.
The other alternative would be the booster solution that Ilkka advocates, and that might actually work very well if the booster were of high enough quality and specifically designed for the purpose. Like Ilkka, I use a Zeiss 3x Classic monocular as a booster, and this would bring the range 75-150x into play with the upcoming zooms. The problems with this setup are first of all the magnification, which should be 2x (giving 50-100x) for the booster for this particular purpose, secondly the loss of light transmission and contrast that come from the addition of quite a number of air-to-glass surfaces, which in the Zeiss aren't even fully multicoated, and thirdly the very narrow field of view that the booster has. I'm sure that a much better dedicated telescope booster could be designed, but I'm less convinced that it would be a better solution than having two zoom eyepieces that would be designed to complement each other.
As far as practical preferences in the field, I will readily admit that I like high powers. I also like wide field, but when forced to choose between the two, and having a scope that takes magnification very well, I choose power. I don't know if I'm just lucky, but I rather frequently find myself using and benefiting from powers in the 50+, 60+ and even 70+ range. For example, just a week or so ago I was in a bird tower around noon, looking at sandpipers on mudflats, and although there was some heat haze in the air I was still benefiting from magnifications around 50x. When a cloud covered the sun, the air stabilized surprisingly quickly, and I soon found myself up at over 70x with perfectly clear and fine images. I find myself unwilling to give up this flexibility with magnification, although I would very much like to have wider fields as well. In the past, I have owned the (then) full range of wide-angle eyepieces for my previous Fieldscope and still have the 38x Wide, but have not used it much on the current scope. But, this is just me, and I understand Ilkka's preference as well and am definitely happy that two zooms that suit it are finally coming out.
As a last comment, limiting the magnification of the zoom to 50x also means that quality issues in the scope itself are not as easy to see. I don't think this is the reason why these zooms are limited to 50x, but when buying such a scope its good to keep in mind if one intends to later use the scope at higher magnifications.
Kimmo
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). I agree with his zoom suggestions (lower magnifications zoom is important for digiscopy…) but my ideal is a sort of Siebert Power Mag Wheel that worked with existing birding scopes. As with astro telescopes 
