We've sold quite a few of them and never had a single return or complaint. We've used them a few mild engine builds, but I'd guess none of them have over 30k street miles at this point.
They don't have provisions for a bolt-on retainer so unless you plan to tack weld the cam gear, I wouldn't use one over 500 HP. Seems like 600ish HP, there is enough load on the cam gear to make them walk off the nose of the cam.