Hi Alex,
you will get a better view, dollar for dollar, from a porro prism binocular rather than a roof prism. If I was looking to buy on a budget I would be looking at porro designs with BAK 4 prisms and fully multi-coated optics.
The only binocular in your list that I recognise is the Nikon Action Ex. I have tried these out a couple of times in shops and I was vary impressed with the quality of the view for what they cost. Their only drawback for me is the weight. The 8x40 is about 30 oz I think. I know you want either 8x or 10x but for a wide field of view the 7x35 Action Ex is excellent (and a bit lighter).
By the way, there is also the Nikon Action which is not waterproof like the Ex, so don't confuse the two.
Everyone on this forum seems to rate highly the Leupold Yosemite, Vortex Raptor and Eagle Optics Raven bins. All porros and all quite light and compact in comparison to the Nikons. They cost around $80-130 I think. They are hard to find in this country so I haven't tried any of them but I would really like to as they have a great reputation. From what I have read about then I think they fit in well with your "a lot for not too much" requirement.
Whether to go for 8x or 10x is a personal choice.
Myself I wouldn't go for 10x because they have less field of view and less depth of field. Also handshake shows up a lot more in 10x. I'd only consider 10x if I was going to use the bins for only seawatching or watching wildfowl on large open water where the birds are very distant. For following hyperactive warblers through the bushes 10x would be impractical.
I think 8x is about right for all types of birding. They have the right balance of mag, fov and depth of view for me. But recently I have been looking 7x bins as I would like to try them to see what the extra fov and depth of fiels are like.
The Vortex Raptors and EO Ravens come in 8.5x if you feel you need a bit more mag.
My requirements for bins are: 8x, fov minimum 390', weight max. about 25 oz
Having said all this, other peoples advice is no substitute for trying out as many bins as you can before deciding. The feel of the bins in your hand and to your eye is more important as the specs on paper. Also the feel and speed of the fucus action is important to me.
So do lots of researches on the forums here and elsewhere to see what is most liked by others and then try as many as you can before you buy and don't rush into anything. That way, hopefully, you'll end up with bins you are happy with first time around.
Good luck in your search and happy birding.
Martin.