I've used Automatic Transmission Exchange for two of my trucks.
1985 4wd Suburban- They gave me a price window for repairing my non-working transmission of at least this much but not more than that much. The removal, rebuild and re-install came in under the big number and the transmission has worked flawlessly for years. And the work was done on time!
1999 4wd Suburban-
I had noise in the transfer case AND rear axle. Again they gave me a price window and the work was done on time and $300 short of the big number. They installed an upgraded rear case on the transfer case to replace the original problematic model. (See the internet)
I recommend these guys to everyone and will use them again if a transmission/transfer case/axle problem ever comes up again. I found out about them from Mark Salem's Trusted Shops website. They are straight shooters, you have to be for Salem to recommend you.