I have a new Remington R-15 in .204 Ruger and am currently running it with a can and a JP adjustable gas block. I am getting tight groups with this setup, but I want to possibly go to an AA gas piston system. Anyone have feedback on the effects of going to a full length gas piston system on their accuracy? Also, is it worth it to go with the free float handguard or is the standard guard in the kit adequate?