And it just occurred to me that Dan was the only one that tried to answer your original question, which are best for the PIII. I have the mato all metal PIII with the stock brass boxes and the HL PIII Tauchpanzer with Imex 3 shaft black steel boxes. Both are airsoft. Both run great. The mato is much closer to scale speed and the brass gearboxes are seriously smooth. It will coast a couple of feet from full throttle! The HL is very quick but it's on Imex electronics and it runs like a dream. I just went to 4 shaft in the PIV and I like them much better than the 3 shaft I took out. Nowhere near as fast, but much more realistic.