FYI, a 4.0 blew on the track yesterday dumping oil everywhere and my lowly S65 seems to do just fine with most 911's (including gt3's) and had a 991s behind me and I lost him (advanced run group so no rookies) and my car has only an exhaust and tune so nothing crazy there and am right around 60 track days with it so its durability shouldn't be in question either and yes I like run-on sentences