I installed a front locker in my TJ over the summer and I always wondered if it was going to completely suck in the ice/snow. Today I finally got to find out since my area got about an inch of snow. Now before people start to complain that an inch is nothing, let me clarify by saying that it has been freezing cold here lately so the snow is nice and packable, not slushy. In unsalted areas it feels like driving on ice since the snow is so dense. Also, I assume the front locker will work in deep snow since there is something to bite into, but I was concerned about under steer in slippery conditions like light snow or ice.
My TJ has 33" MT claws, front richmond no-slip locker, trac-lock posi in the rear.
In 2wd I could spin the TJ with no problem, and I couldn't hit the gas hard without losing all traction. Once I engaged 4wd I prepared for under steer but to my surprise I could steer fine. If I kept constant pressure on the gas pedal the TJ was perfectly neutral in turns, no under or over steer. The only time I had under steer was when I hammered the gas in turns trying to make it under steer. I played around for about 45 minutes and I feel really god about the locker now. I don't plan on using 4wd unless I really need it in the snow, but now I know that its not as bad as I expected. In fact, its pretty predictable.
... I also know now that these claws are horrible for traction compared to my A/T's in light snow, haha. I guess tread sipes really do work.