Just like everyone else, I too have lusted for lockouts, but the benefits just don't justify the costs IMO. I'm not saying that anyone shouldn't buy them if that's what they want, just don't try to claim any money savings in any less than a half million miles of driving and by then the Dodge that your Cummins is wrapped in is gonna be pretty well, overall clapped out anyway.
It's also my opinion that the price of the lockout conversion kits is much higher than it needs to be because of the typical high cost of replacing these OEM bearings from the dealer, the conversion kit price being the most that the market will bear based upon the known high cost of replacing the OEM bearing assemblies when needed. On that thought, I wonder if the price of the kits will come down any now that many sources of much lower priced bearing hub assemblies are available? I also wonder if anyone has tried to do any backward engineering against other vehicles which ran Dana 60 front axles and had lockouts? Doesn't have to be a Dodge. Might have to adjust some dimensions to fit the AAM axles but I'll bet it's not brain surgery. Maybe 1980s Cheby parts?