I tell you if I still lived in Alaska & still worked for the oil company, especially up in Prudhoe Bay or in the bush down line somewhere, I would have them tomorrow, $25k is well worth not getting stuck out in the freezing snow/ice in -50*f trying to get your rig out of a snow drift/bank or muskeg... they look pretty easy to install, seems kind of pricey thou... may come down in cost they are just now becoming available... but the price is better than having to convert your rig to a track vehicle & only be able to use it select weather, then have to convert back... Also they say it's not tested in mud, but they think you will get premature wear in sand &/or mud, they can be driven on pavement @ something like 30mph recommended speeds & snow @ like 40mph recommended speeds... will fit 31-35" tires & up-to 13" wide, a couple of rubber track stops & brackets need to be temporarily installed on the rockers in front on the pinch welds bolted down by compression clamps & the leaf springs in back {they are made for rear leaf springs only IIRC}, they can handle like 12k GVW weight 325# each & full installation adds like 1375#'s, must be 4WD & have a locker in the rear optional in front IIRC...
