[mcguyver]

I've run at least 30,000 rounds through my CQB-R, mostly with M130 (about 20K) and M110 (about 10K) and the rubber was still OK when I checked it this spring.

I guess it would stand to reason that with the heavier BB, more pressure is required which means the rubber will wear faster. But, considering a replacement cage/roller is about $12-$15, a once-per-year replacement won't break the bank.

If you like the performance of the 0.28s vs the 0.25s, I would stick with the 0.28s and just replace that roller as part of an annual maintenance.

And Metal Tech has not chopped, misfed or jammed on me once. KSC Perfect 0.25s were another story. If you have consistant jamming or misfeeding, check the barrel alignment. I've fixed that one before, and on the field yet during a game.