My 410 has the 475kit from hangar 111 with there trackday rear silencer full exhaust system heat coated from zircotec since year September and im loving it.
When i spoke to komo tec before getting the kit they where very helpful on the phone. They have done many 475kits some cars with a lot of track miles on them with no problems. They where saying 475 is a reliable number any more power like the other gentleman was saying you will start to push it limits.
To be honest i was going do i write up after getting my car back from hangar 111 with my 475kit but iv been so tie