i'm thinking of getting this: http://www.performancebike.com/shop/...tegory_ID=4120 trainer. by my understanding i need one manufactured by minoura because my tires have too much tread and wouldn't work well on the other types. has anyone else used a trainer, or specifically one from minoura? are they quality? am i paying too much, or any thing i should be aware of before i make a big purchase like this? thanks.