Hi Breakpoint,
Count me in. Finally switched fully to the K90. It took about 3-4 months of playing with it off and on, matches, etc. to finally get the serve worked out. For me at least, the weight of the racket needs to be handled just right for serving and overheads, so took some time to get the biomechanics worked out. Now I can put the ball where I want, down the middle, into the body or out wide and plenty of spin on second serves. So I'm selling all the rest (check the "for sale" section).
I have been using Bab Hurricane Pro 18 at 54 lbs. mostly, which I liked quite well. Also tried VS+ mains and HPro 18 x's - nice combination, but I don't like the strings moving around. Currently experimenting with Bab Hurricane Tour 17's at 53 and 55 (bought the second K90 a couple days ago). I was looking for a little more bite from the strings and better control - so far so good.
Just can't beat the K90 for solidity, placement and hitting a heavy ball. As Granville said in the review, it is like having the biggest weapon on court. Ultimately I just feel more confident wielding a racket that will handle about anything thrown at it (or hit!). No problem with headsize. BTW, I did get an AK90 which is a very sweet racket. Not stable enough though. I found myself having to put more energy into holding the racket more tightly to keep it from being knocked around. US K90 no worries, just stick it out there (it's so nice out I think I'll leave it out
) and the racket will do the rest of the work - just fantastic! So I am finally a devotee and (for now) my racquoholic days are over, at last!
Long live the 90's.