If the belt only lasted 3 1/3 months there is something causing it to fail. Check the condition of your pulleys, and make sure they're all lined up porpperly (i.e. none of them stick out further than the others). If you have a damaged pulley it will likely damage the belt. What kind of shape was the belt in? Did it appear cracked or burnned? I see you're in the U.K. so I guess that'd be 'burnt.' Either way, sounds like something besides the belt is causing your problem. Do you have a spring tensioner or do you have to tighten the belts manually? Maybe it was simply too loose. Gates belts are good. Check all your pulleys closely and the tensioner as well. Make sure there are no barbs/scratches on one ot the pulleys that are chewing up your belt.