Did you turn the idle speed down to what you'd like it, yet?
If not, do that and report back.
That's what I'd do, anyway.
I have a K7, and I just this afternoon installed a Power Commander to go along with the beefy-sounding Leo Vince Hi-mount Ti slip-on I installed Friday night.
I haven't ridden it yet because of salty roads (though I'd love to), but when I started mine, the ISC valve (auto idle speed adjuster thingy on the 2007 models) had the bike idling nice n' smooth at the usual RPM.
Also, if you ain't liking any popping with the new can, go for a PAIR eliminator kit.
I did this when the tank was lifted up for the installation of the other stuff, too, and this is supposed to get rid of popping.
I'll find out soon enough.