I've had several sets of varying quality over the years. For bird watching I'd be after something with a good field of view and quality glass. You can spend a fortune on bins but save for an extra month or two and go a little up market (and) or look at 2nd hand, you'll find a world of clarity not available at the lower end of the market. January and February are good for 2nd hand deals.
I was after a proper set this year but had to rationalise my ambition with the fact that I'm an occasional user so for me quality bins are a luxury.
A keeper pal got a new set of 8 x 40's 20 years or so back, I asked if I could look through his old set, which I was did looking up at a munro on a clear day and I could see figures on the summit but there was a lot of haze and I couldn't make out any detail, he let me look through his new zeiss bins and as if by magic I could make out the colour of the clothing worn by the summiters make out their movement direction of travel etc, the haze was much reduced, a mass more detail, and I've been after something of that quality ever since.
In the end, and after much sole searching and binocular gazing, this year I found and settled on a set of Minox HG 8 x 43, not cheap, but not £1200 either. I'm more than delighted tbh, I've wasted almost as much on poor bins in my time, every time I look through the now new-ish set I feel a little spoiled, and rather smug if I'm honest
So I guess what I'm saying is try them all, and be prepared to delay purchase and save a little more if you find something that does it for you .