Ted, I've tried the P94, the Phat Cat and the P90.
You have to realize that there is no "p90" sound, as much as there is no true PAF sound. The pickups have been very variable over the years. I fellow I know (Voxman) has a nice collection of older P90s and they run all over the place in both DC resistance (from about 8k to about 14k) and in magnet type/strength. Some are very sweet toned, while others are agressive and uber-raunchy.
The Phat Cats tend to be sweeter toned, a bit light in output, and very balanced... think of them in terms of a lighter wound P90. The P94 (Gibson) is very hot, raunchy, screams, thumps, blisters. Think of it as a hotwind P90 tone.
I love the Phats in my Gibson ES-333 (like a 335, only no appointments). However, in a solid body, I'd pick the P94 any day.