Yesterday I broke my outer drive shaft on my Summit VXL, easy fix but it cost me 12.00 for the part. Tonight, I broke my inside drive shaft. Any recommendations on an upgrade to eliminate these issues on my Summit without constantly replacing the plastic ones? I've been reading a lot of the MERV metal shafts, but I understand you need to change a couple of other components from a MERV. What's the easiest upgrade/fix?