I went with the 700R4. I was told, by several knowledgeable mechanics(not hobbyists) that the 200 is just not as durable and won't handle the abuse. (I have a fairly stout build, and WILL abuse when I can)

Also added the lock-up convertor, which saves about 200 or so RPM at highway speed.

I have a 3:55 rear end. Changed to cross member, driveshaft, added adapter for bolt pattern, and added bracket and modified throttle linkage geometry to work with the TV Cable.