I love ESEE and KA-BAR, own a bunch of both brands and can honestly say it's up to how much you want to spend, I find edge holding / toughness are pretty much the same, so that's a draw.
With ESEE you get an awesome sheath / micarta grips stock so no need to go out and purchase those separate, but it also comes with a higher initial purchase price, with Becker you get a great blade with a lower price, but if you want a better sheath / micarta they cost extra, and in the end both the ESEE and Becker cost about the same if you include a custom sheath / micarta.
I own an IZULA II and can say nothing but good things about it, I recently used it as my main knife on a 2 week trip in north western Montana and it did everything I asked of it.
Like I said, it depends on how much you want to spend initially, I find Beckers are more of a "Kit" knife that you mod / customize to how you like it, not saying you can't do it with an ESEE.