My point was no matter what kind of cam you run, when you push over 6500 rpm things get 'expensive'. You need a good bottom end, great heads, those bee hive springs I've been reading about look real good. The faster you go, the more it cost, and reliability becomes a factor to reckon with!
I built my motor on a budget and with longevity in mind. 6200-6400 is a reasonably safe range for a side oiler and a long life. 3 years ago, or so, a hydraulic roller cam in the 6200 rpm range would have cost a lot more than my flat tappet. Solid roller lifters have come a long way in the last 3 years as well. Longevity is up and the cost is coming down.
While my old motor would turn 7000 plus (solid roller), I gotta tell ya, it scared the heck out of me taking it that high. It was a rare trip to that lofty region. Like when I'd leave it in third gear and run 'out the back door' at the end of the strip. Whew, scary stuff.
500 plus horse under 6000 rpm, sounds like a GREAT motor to me!