I've used the basic BD manual TC lock up system for 8 years, and wouldn't be without it. This newer version in your link has some additional capabilities, however, it doesn't address your complaint (which I also have) of the PCM initiating a torque demand down shift when you get on it a little too hard going up a hill. It will keep the TC locked when this downshift occurs, but this is bad because when the tranny shifts UNDER LOAD with the TC locked it scuffs the tranny clutches and jerks the drive line.

I tow with the TC locked using my switch, and I've gotten pretty good at pushing just hard enough up a grade so as to avoid the PCM controlled downshift, and knowing when I need to manually downshift to third before the PCM does it for me. I keep the TC locked when I make the shift, but I let off the throttle first to unload the drive line to avoid the jerk and extra tranny wear, and then slowly get back on the throttle again after downshifting.

I visited DP Tuner for a week, and Jody tried several approaches to give me a special tune to inhibit the PCM commanded downshift and let me have control of when to do it using the OD lock out button. It turned out to be a much tougher nut to crack than he thought it would be when he told me to stop by Asheville and he'd fix me up with a special program to let me shift my auto like a manual tranny. He did figure something that was a little better than what I had, and I've got 7 positions to play with and I'm very happy with my DP, but I'm still looking for a better solution so if you come across one let me know at kempegenek@gmail.com