I have heard alot of people raving about the transcommand. I have played around, burned up and rebuilt one of my 4R100's. I never got the shift firmness or coverter lock with an external control. My rebuild has fantastic shifts and converter lock. I do use my own lockup device. The sonnex shift valves, pressure valve and front pump to converter lock pressure valve. I didn't use the sonnex springs because my trans had a Fairbanks kit already. I don't know how much the banks unit cost. I only have $300.00 in the parts to rebuild the trans.