lt1s10

Do you know what parts are breaking internally and causing you to have to rebuild it? If you're breaking internal parts or burning clutches and the band then it's usually easier to build a TH350 strong for less money then the 700. But if it's the electronics (shift solenoids) that's giving you trouble you should be able to trade your electronic core for the non electronic version and rebuild it one last time and be done with it. And still retain overdrive.

Lots of people run high horsepower/high torque through the 700r4 they just need to be built to take it. It doesn't cost a lot more to upgrade parts during a rebuild since the labor is the same and usually the expensive part of the job. Also if you want to add an external trans cooler you can run it in line with the radiator trans cooler. And that makes hooking up hoses a lot easier since it's all up front and you still retain the factory hoses coming off the trans.

Edit: You may need to check on how your speedometer works with the trans sensor and the instrument cluster. If it's electronic you may need to get a converter to use the TH350 since the TH350 is a mechanical gear driven speed sensor.