I had a pair of 661s -- not sure which ones. I ripped through the velcro straps in about a month and a half. I ride XC and I don't think I was being to hard on them. After that, I wouldn't recommend them. Now I'm sporting a pair of Shimano M225s based on a friend's recommendation. They fit well, feel solid while on the bike and can handle a short hike if necessary. They've held up much better than the 661s. Based on the two experiences, I'd suggest something by Shimano.