I have a 700r4 I bought from them almost two years ago, there were some issues, but it had more to do with personality issues than product. What are you trying to convert from and what kind of power are you going to make? Personally, I wish I had gone with the 2004r since it would have bolted right in place of my PG, and the gearing is spaced better IMO. I don't have a huge motor or anything, so that wasn't an issue to me.
So far, I've had no problems with the stuff I bought from Bowtie, and I bought everything there!
Feel free to email me if you want more info.
Colorado Springs, CO
68 Camaro... someday!
71 Chevelle SS