Purchasing Xb 700 ???

I'm considenring upgrading my Xtreme 508 to an Xtreme 700, but am heisitant to spend the money. My 508 recently quit just short of 1 year and around 1000 miles. Apparently I need a new controller (per tech support). I've also read several reviews that have pointed out many "quality control" issues with the 700. I don't want to spend 1600+ for a bike that's not going to last..anyone have any thoughts? Is the xtreme 700 worh the price?