I just ordered the Regal 100mm, figuring it would give a little better performance over the 80mm version. Weight and size were not that big of a factor for us, seeing it will be used primarily as a house scope. Still, I wish I had heard from someone who actually used the 100mm model before ordering. My best opinions came from people who had actually used or tested the 80mm or 65mm version.
The scope is supposed to arrive on or before Jan. 15, and if anyone is intrested, I would be happy to share my opinion on this one when I get it.
I saw the thread so thought I'd chime in. I used the 100mm version. My results are very much the same as others who have used the other sizes of the Regal.
1. Optically, very enjoyable. Not exquisite like an Alpha, soft at full zoom but still appropriate levels of performance at typical scope magnifications.
2. Very stiff "coarse" focus knob / very nice "fine" focus.
3. The coarse focus is positioned such that you basically have to forcefully use your thumb. The fine focus is really perfect but it's hard to know which direction to focus due to the slow response, so coarse focus is required and does take some getting used to.
4. Heavy but not an issue if in a fixed location.
5. Very front heavy - it comes with a balancing bar, which is ok, but if you have a quick release type tripod connection, it may not have enough room to perfectly balance. It's easy to tweak "close enough".
6. It's built like a tank. Nothing seems flimsy other than the somewhat garbage soft case it comes with.
On the weight, one must wonder why a scope like the Pentax 65ED can be so light and then a very similar model like the Regal 65mm can be so heavy. It's not just the material, as other similar models aren't as heavy. I really question whether the designers considered the intended usage. In any event, I think you'll enjoy it, especially for the prices they are out there for.
Feel free to PM me with any specific questions.
Matt