I'm new to biking and ride a Giant Warp (its a hardtail). I have not modified the bike at all. I am 6'6" tall weigh about 250lbs. I ride singletrack and am as aggresive as my skills will allow me to be. I keep "warping" my rear rim. I get it straightned at the LBS, and after just 1 or 2 rides its wobbling like hell. Well I need to know what type of rim to buy. Are the 36 spoke ones really that much stronger. What about those 3 or 4 spoked composite looking rims? I want one that will allow me to get wild on the trail and not buckle except under the most extreme drops.