they are really about the same difficulty to swap. i would go with the 200-r4 because it can be built to take just as much, if not more, power than a 700. also the 200 is a close ratio trans, resulting in better OVERALL acceleration. yes the 700 has a .81 higher ratio first gear but when it shifts to second you are now below the torque band giving less acceleration. also, except for a few corvette units the 700 will not go to overdrive in WOT, the 200 will. not that you'll need that too often. just make sure that you get a 86 or newer 200-r4 (if getting a used one) as they have the upgrades and fixes already in them.