ChevyII
The vette and camaro with 350 are better than the rest. The vette tranny in particular, however, any 89 and up 700R4 can be upgraded to be equal or better than anything that GM put out. It does take a bit of reading and work.
Sonax and Superior make part to upgrade these units. The superior super servo for 2nd and 4th really help these units live. For a daily driver a 0.471" boost valve is a good choice. For a hot-rod type application the 0.500" boost valve is best, this along with a good valve body shift kit really wakes these transmission up.
I bought most of my parts from these folks - very easy to deal with and they will answer questions. Just try and do a little home work before you call.
http://www.transmissioncenter.net/highperf700r4.htm
