my buddy put one in his work truck when the stock carrier broke. He does basment work. They haul around a lot of stuff in the bed of the truck and pull heavy trailer.(bob cat,mini-X's and such) He loved the tru-trac in the rear axle. He said you could not tell it was there untill you got on the gas hard and it would light up both of tires everytime.
I had one in the front of my off-road jeep that I got used and I use it for about 3 year. The case broke b/c it was ment for a C-clip axle and did not have as many gears in it as it would for something that is not a C-clip alxe(like the 10 bolt I am runing) I know if I was to buy something for my truck I would buy a tru-trac. Also you do not need any spec. stuff to put in for clutches since there are none.