To those who ride a cbr, what exhaust do you have? I'm planning to upgrade the stock exhaust of my newly acquired 2008 cbr600 and I can't decide between the Yoshimura, FMF and Two Brothers. Any suggestions? I'm planning to get the slip-on at 4 wheel online because of their offered price. If you have other suggestion, let me know but let's keep the budget at around $500. Thanks.