I've used B&M and TCI on Ford C4 and C6 transmissions. Both are equal as far as I am concerned tho I do think the TCI instructions need some help. I agree with Denny. The trans has to be in good shape with clear/clean oil and good shifts before the mod - it isn't a band-aid for one that needs overhaul. The lowest stage is sufficiant for basically stock engines and a stock or low stall converter and street or towing. I have for years been using TCI SFI flex plates, their Saturday Night Special torque converters and Street Fighter transmissions with great luck