IMO, a bad 700R4 is a blessing. With all the updated parts available, you can now build a pretty fantastic overdrive automatic. I'd suggest you look at all 3 websites before you make the final decision. I'd also recommend having the strongest version built. It only amounts to a few hundred extra, and over the life of the trans, well worth it.
Look into replacing the drum that the 4th gear brake band runs on, and buy the newest version of that band which is now the full width of the drum. There are other trick parts available too, so do your research and learn about what's being built. Personally, I don't see that Monster has the developed website that bowties and raptor have. If I were a customer, that would concern me.
What ever you do, follow up with a new TV cable, and install it using a pressure gauge, as instructions detail on the bowtie website. Any other method is not correct, and it's the death of a 700R4. Also, look at the cast aluminum finned B&M transmission pan that holds 3.5 extra quarts and is bunged for a mechanical trans temp gauge. Lastly, look at the big Tru-Cool or B&M Super Cooler (same cooler, made by LONG, but boxed for either company) and fit the big 11x11x1.5" thick cooler up in front of the a/c condensor. Mount the cooler with the lines coming in from the side, or the top, not from the bottom.