skruface wrote something about boreups a while back but some others did not agree, hold on let me find it. I don't know if it is still valid, but when I had a choice of cylinder sets I chose a reg set because I was sticking to stock barrel. I think the moral is you *might* have to upgrade the spring too.
edit:
skruface:
http://airsoftcanada.com/showthread.php?t=2697 <--great reading btw
*NOTE* There is a cylinder type called a Bore Up Cylinder. This has a larger inner diameter, meaning it can hold more air volume in the same length of stroke. However, it requires a VERY strong spring to work effectively - the Systema M130, which is far too powerful for use in our games. DON'T get the Bore-Up Cylinder, it's a waste of money for 95% of you.