Honestly, if it works, dont mess around with lighter bolts and different springs etc. For the sake of running it on a slightly lower psi, it never seems to shoot all that great over the stock stuff. If you want a new stock bolt/spring or whatever, you can contact KEE Europe direct and Im sure they will be able to help you.
If you wanted a board upgrade, the new Shockwave board from Empire is pretty sweet, and in the states its like $26 so pretty cheap. Its better, easier to programme and little things like if you take the battery out, you no longer lose your settings. Ive used one, works great!
Only other thing I changed was the trigger. Bought a roller bearing one, just to take the slop out the stock one had.
