Alza cd for sure it's worth every penny. Tcs crawlers makes really nice 5mm tvps I have the standard length and have no issues with them. The xl ones come in many different colors. I use the stock 2200 motor and esc that came with the savage flux I started with. The alza cd has completely eliminated my breaking of the pinion gear in the rear diff which I did a lot of. Btw alza parts quality is second to none. You wouldn't do wrong with their tvps either.