i was doing some reading about springs, and it makes sense that i may need to replace my sagging springs when i replace my shocks with the AGX's... can i use stock springs with these shocks, are the springs on ebay ok, how could an expensive spring differ that greatly from the cheaper ones (aside from material i guess).. anyone selling their springs?? i posted in the classifieds for wanted springs. my email ultradtb3000@yahoo.com.