Just looked at your website, and noticed you are planning on getting the Pro 120 speed controllers *at this point everyone else knows what Im thinking about saying* but just for your benifit I would be careful in your choice as Ive learnt the hard way. I sent 3 off to be fixed last month and we have 3 in our robot and have 4 spares just in case. Some people dont have any problems with them but whatever the reason we do. Having said that we are still using them.

Im assuming the interface/mixer you are talking about is the 4QD one. Is this the one that requires servos to move pots? If so Id aviod that one, there are much better ones out there. I built my own and this provides the failsafes.