I`ve has a CZ-40P for a few years. It serves as a HD weapon with a Streamlight M3 on it. I`ve also has a 75B for years so I can compare/contrast them for you. Both are very fine weapons. Don`t be scared off by inane "franken gun" talk.
Major firearms companies combine parts of their various weapons into new configurations every day but they usually give them catchy names and charge a hefty premium for them!
The 40P frame doesn`t have a smaller grip frame,just a shorter one. It has a pronounced beavertail which I like because I tend to use a very high grip. The rest of the frame is much thicker than a steel frame CZ or even the PCR,making the 40P chubby like a Glock. Honestly I find the heavier but more svelt 75B easier and more comfortable to carry. The PO-1 was the first CZ series to be make without the hand fitting that CZ was known for. This as a result of Czech gov`t requirements. This may be one reason the trigger of PO-1s and 40Ps is rather lackluster out of the box. I dry fired mine with snap caps a LOT,which helped a great deal but even after 1,500rds. or so it`s still not as good as my 75B. That`s not to say it isn`t very adequate,just that the 75B is darn good. The 40P is quite accurate,more so than most service autos. The 75B is even more so. For a carry gun I`d cough up the extra bucks for a PCR,unless you really have your heart set on a .40. For a range/target gun that you can also carry,I`d suggest a 75B. If you want a .40cal. CZ with a light rail for a great price get a 40P. That`s why I bought mine.
Marcus