true our balancers are superior to a straight up aluminum piece. even better than ours are fluid dampers.
but these are for built engines, preferably balanced very well (as mine is, and his.)
hes been running the crappy OBX pulley for 3 years, and was tired of not having enough alternator power and his other accessories spinnin so slow. so he got a balancer from me and made a full size.
if your motor is built right, then running this for a period of time shouldnt be a big issue. biggest strain will be on the bearings, and if you get good bearings it wont be and issue for a good amount of time.
but like i said, these wouldnt be a bolt-on for a 20+year old engine. these would be if you have a moderate to highly built motor and have taken all factors into consideration.
the fact that my freind has been running his for so long with NO problems is a testament to that fact.
but i just figured id put this out there for anyone whos interested