I do not have the problem with the jerky engagements or popping that you guys are explaining. My detroit engages with about 1/4 of a turn of a tire, is engaged the whole time I am on the throttle, and disengages smoothly when I let off the gas. I do not get the Jerky feeling that everyone complains about. I have yet to have the ass end of my truck walk out in snow or ice, and that is with a few years worth of Upper Michigan winters. Maybe the fact that mine is a long wheelbase helps to reduce the tendency? I dunno, but I have no complaints with my locker. Is a spool more predictable, yes. Is either better, depends on what you want. They are both harder on axles. A selectable is the best, hands down, but mucho $$$. This is kind of a case of Six of one-half dozen of the other. Would I ever own another vehicle with out some sort of traction device in at least the rear axle, no.