If you like throwing money away, go with the PDX1. The performance of different bullets can vary greatly with caliber and velocity, just because the FBI uses the PDX1 in their service weapons, doesn't meant that the 9mm version is just as good. Just google some ballistic tests with the 9mm HST, they are far superior than the PDX1 in cavitation, expansion and penetration when shooting at ballistic gel. FBI uses the PDX1 because they are more likely to shoot through barrier and bonded bullets perform better. But the federal HST is the most common bullet used by LE. I have read that the PDX1 has some failure to properly expand issues as well. The answer is pretty obvious. And for some reason if you really have to shoot through barrier, the HST will still do it's job. I also suggest putting a magazine of the SD bullet you are going to use through the gun you are going to defend our life at the end of every trip to the range, so being 1/2 the price could add up in the long run.
As for recoil being more on the federal hst, you are probably shooting the +P version. The recoil should the same/similar between the HST and PDX1 in 147gr since muzzle velocity for both is 1000 fps.
Federal HST 147gr expansion through ballistic gel. So pretty...
http://le.atk.com/wound_ballistics/load_comparison/images/P9HST2_147gr_Wall.jpg