I've ALWAYS been a loyal Hoover user, & THIS model is the BEST by far! GREAT suction power, fantastic attachments, the quietest I've ever owned (I can easily hear the phone ringing!) & light-weight enough for stairs! But this one (purchased a month ago) is giving me a slight problem - the belt "slides" off of the shaft easily & quite often. Sure, it's easy to replace, just 6 screws, but it's becoming time consuming, having to stop & replace the belt 3 to 4 times per cleaning session. It looks to me that there's nothing to keep it from sliding off, like a "lip". Also, this is the first beater bar I've seen with a convex'd bar where the belt runs. Shouldn't it be slightly "concave"? Is something missing from MY unit?? Please help, for other than this factor, it's the BEST vacuum EVER... no matter the price/especially the price!!