The 200 has a better gear ratio pattern than the 700. The 200 is similar to the TH350/TH400, where the 700 has a big drop from first to second gear. And they can both be built stronger than you will ever need with that combo. A stock 700 would survive behind that motor, but it would be at it's limits. Same with a stock 200. The 200 is also an easier bolt in. (same drive shaft, and a modified 400 cross-member)
Correction, the 200r4 is not the same as a TH400 or same driveshaft link.
It shares the same drive shaft length with the TH350...... The 200r4 and TH350 are one of the few tranny swaps you can make that pretty much all that is nec is to slide the crossmember back a few, and find a way to run the coolant lines......
The 700r4 and 4l60e are pretty much the same
both are still weak in there stock form ........ rating of 365lbTQ max
go to ls1 tech, ls1truck, ls1gto, and ask those guys how many times they have had to rebuild their 4l60E's?
Now the ones that are hard to find and a little better 4l65E and 4l70E, they come stock with some of the added goodies.........
Put the 200r4 in and forget about it, your not going to be driving around on the street at the 450HP level at 6000 rpms all the time ........ think real world. Plus its not about the horsepower that tears up these tranny's, its the torque......