I personally would not want to run a lot of +P ammunition through a Kel Tec 9mm. Yes, I'm sure other people have, and if you had a pocket Glock sure, but the Kel Tec products aren't exactly the sturdiest products made. (And yes, I did used to own a P-11, had a P32 and my wife has a P3AT.)

I'd look at either standard pressure 147 grain JHPs - if you felt that they'd reliably expand at whatever velocities the KT drives them at. If you want to hotrod the 9mm, I'm not sure that the KT is the right platform.