It's funny to see my thread bumped from 4 years ago. Buscrusher, I don't think that person was offering up a GearMaster II, just letting me know what they were and this was 4 years ago.
I almost gave in so many times to getting a Gear Master II which I think I would have appreciated, but never did. I never did see any come up used in the time I owned the truck and was keeping an eye out for them. Overall I got very comfortable with shifting the 10 spd. I would occasionally have my moments when I was rushing things or getting flustered, but if I slowed down and just took my time, I had no issues. I never did get my wife comfortable with shifting the truck and that ended up being why we got rid of it plus we wanted a pickup for a truck camper. We tried a few times and she finally gave up and refused to try again. She did drive an iShift truck at at the ECR and enjoyed it, but just decided the manual wasn't for her and wouldn't try again. I actually took other friends out and got them to figure out the basics.
We sold the HDT last year and the new owner loves it to pull his very large Momentum Toy Hauler. I definitely miss driving it and I really miss hauling a 5th wheel with it. There just is no comparison with towing with an HDT vs a pickup. That 610 singled short was the perfect size for what we used it for. It was fun reading my story again about picking it up.
Funny tidbit, my friend Scott that helped me drive the truck back to GA. Him and his wife decided to go full time 2 years after we did and we are actually hanging out with them right now in Salida, CO. They've had 3 RV's in 2 years and just got back into a 5th wheel after a large Class A DP. He was considering a HDT himself, but I think he's found a Ram 3500 he's going to get.