Hi Les, I have Futaba 4 Ch with the Tri Pact. The Tri Pact is all or nothing and takes two servos but it is dirt cheap and reliable. There are robot style mixers which save a servo and Tankzone does a 2 motor proportional @ £90 I think. Will you need 45% of your speed during combat? Check out rctankcombat.com, lots of tips for big scale stuff there. My M1A2 was originally an Hailaing No.3088 1:12 scale bought off ebay, you know the one with rockets on top, oil drum on the back and the Frankenstein Commander. Soon stripped it and got it looking and doing what I want! I will be sad when it's finished! Dino. [8D]