I find longevity problems in most shimano's. Yes they are quality built but often replaced. They purposely relieve themselves of spareparts. By the time you need a part, admittedly a few years down the pike, they are hard to find. I couldnt get a new bail arm for a CI4 for over 2 years and thats while it was still in production. According to their wholesalers, they could get it but shimano refused to sell it to me. I wont touch a shimano again.