The TBDs are awesome in the snow and on ice. We do ice track days and it's really cool. I have posted photos somewhere....
I ran Truetracs in my offroad Range Rover for 8 years.... and the only time I wished for real lockers were when the axles were crossed so that two wheels had little or no traction at all. Anything times zero will always be zero .-).
I may be biased, but I really like the diffs
I just used an angle grinder to cut the drive shaft. The heat genereted only affects very small distance - and it's not even loaded in this application.
The gear ratio change needs to be taken into account in the TCU firmware. Otherwise the TCU will think the planetary center diff is slipping all the time. The front speed pickup is located at the diff carrier - not the pinion.
The QC and the power mod will not affect this in any way.
Talk to Mike.
Cheers,
/T