Just my 2 cents... My main Explorer has has had Mile Markers for years and while I don't offroad it heavily, I've used it on dry dirt, through a few winters (some wet pavement use) and the previous owner used it to haul wood that he cut in the forest with a trailer. They've seen some good use and haven't complained yet.
My other Explorer has Mile Markers and they were locked in when I got it and I assume they were left in that way 24/7. That truck is beat to hell and I'm sure the hubs and whole drivetrain has seen abuse on dry pavement. To give a rough indication, the rotors were eaten at by pads that lost all their material, ball joints are bad, radius arm bushings are gone, tires and wheels mismatched and the transmission fluid felt like liquid sandpaper. Plenty of abuse and lack of maintenance.
I also have had a good experience with Mile Marker customer support. I was able to buy o-rings from them over the phone and they shipped out quick and for a good price.
If I was building an offroad truck, I'd probably have the budget and go with Warn. However, for a daily driver or occasional weekend camper, I wouldn't hesitate to go with Mile Marker.
