I usually just stay in 6th because you can pass adequately fast without downshifting. That being said, if I'm showing off for a friend or just feel like smoking someone I'll drop down to 4th and then quickly shift up to 5th as I hit 5500 RPMs or so. One thing to note, though, is that our highways are 65mph so I'm usually behind some slow-body at 65 when I pass.
-Carraig
-Carraig