Hey, I'll happily chime in. I've got a 92 extra cab 4x4 with a lift. I went to a 1 piece driveshaft about 100k miles ago and have no problems. I'm not sure what the length is, but if you want any info I'll get it for you. Driveline Service in Sacramento built it for me. I did have some issues with vibration, but they went out of their way to resolve said issues. Bottom line is that a 1 piece is a common mod and there should not have been any failures.

Good luck with these guys. I hope they decide to do the right thing.