I've going on 6 years on my Ohio Crank 499" kit, with only one freshen-up. I drive it a couple of thousand miles a year and race a KOS class about once a month. It dynoed at 520 RWHP and has ran a best of 6.89 and 104.1. The bottom end has iron main caps and, of course, ARP bolts. After reading accounts on here, I am very happy with its durability.