my buddy ran stage 4 kits on 2 of his 2014 pro's. never did get them running right. traded both in for 2015's and didn't install and stage kits. he was down and out more last year due to the stage 4 kits then he rode.
Youll have much more luck with the MTNTK full mod. makes better power than the SLP stage 4 and is less money. Talk to Shawn at MTNTK. He will get you set up. There kits run flawless. I have ridden both and the MTNTK ran better and made way better bottom end torque!