The EFK unit I bought for my P226 .40sw was crap. Don't buy it. It was nearly impossible to rack the slide to chamber a new round, and it rattles around like crazy when you shake the gun in all directions, indicating the rod/spring assembly wasn't properly seated. Every shot I fired resulted in a FTF. That was $80 wasted.
If you're interested in a recoil-reducing rod/spring system, I'd try
http://www.dpmsystemsonline.com
If not, I'd stick with the factory set-up.