Posi unit question

[400ex]

Need information on Auburn Posi units for my 12 bolt. Just called Pyle Brothers nea Houston. I want them to rebuild the rear with all new parts.
He said they would use an Auburn posi. Weird thing was he said not to do a burnout while holding the brakes. He said something to the effect that since Auburn's are cone style units (they grow with inertia to lock the axles) it would grenade the rear if that was done a lot.

Well, that got me wandering if Auburns are all that good now. Dont get me wrong, I dont hold the brake when burning out for very long. Get it spinning and let off the brake..

Anyone have issues the Auburn posi? Should I look into an Eaton unit?

Any information on Auburn posi reliability appreciated..

Thanks

James