The powercore is just a tad on the loud side and I'm thinking of either getting a silencer slip in or maybe eventually going to a Q4 if they are a lot quieter. I just don't want to give up any power advantage!

My Q4 is not a bother to me, I'd buy it again without hesitation, but it's loud enough. Early on I test rode a bike with a Powercore; it WAS a bother to me; said right then I'd never own one.

Sarah

The Q4 is quieter, but you'll trade some performance.
No two ways about it.
It still has more performance than the stock muffler, though.

Change the header to a megabomb or powerbomb, FMF advertises both as quieting down the exhaust, and if thats not enough add the quiet insert (which will hurt performance).

having heard the powerbomb plus pc4 and megabomb plus pc4 the megabomb is by far quieter.
the only difference, besides mentioned, is the megabomb bike had a pc5 and the powerbomb a fmf controller.