I'd be surprised if diff in resolution (none of these are crap optics) was the issue. 10x, if otherwise comparing apples-to-apples, will give you more detail, but there is a valid point in saying that hand-shake will negate the improvement. THAT's totally dependent on the user. I'm typically hiking/birding, and getting older, so the 10's are a no-go. But I have owned 8 and 10x in same bino (Trinovid HD's and Noctivids), with opportunity to compare. I ended up selling off the 10's.
I would also caution against discarding a particular brand or model based on one or two BF reviews/comments. As example (sorry Dennis), Denco points out 'blue ring of death' with SFL's (we own 3 SFL's and find them to be the best bins for us and our style of birding, regardless of $$), yet recommends Swaro NL's - which several respectable reviewers have pointed out to have veiling glare issues. Just saying the latter, will quickly bring out NL defenders and this thread will get very lively
As soon as you move into the Conquest/MHG range (and above), the differences start to become 'academic'. They are real and they are there and you pay dearly for them, but it's more important to find bins where you like the ergos, flat vs pincushion view, warranty, etc.
A personal example: I dearly love the Leica 'look' (and build). But yesterday as I was using my 7X retros in front yard, I noted a Blue-gray Gnatcatcher flitting about in small evergreen. They're
fast, the foliage was dense, and by the time I chased it with the Retros, I had missed it. It would not have happened with the SFL or FL or SF's which have FAST focusing with BIG grippy knobs. I still love the Retros for their qualities, but for hardcore birding I'll take the 30/40 SFL's all day long. I say that after having owned many (not all) of the rest of the obvious possibilities with the exception of Swaro.
...best to fondle some bins, provide honest appraisal of budget and intended use, and then decide ;-)