I have the Cooper Evolution M/Ts. If you are doing some serious offroading and air down quite a bit, they are a great choice. Burly, tires with big, meaty lugs. They are ok in deeper snow, but don't have enough siping to really grab and hold snow for good friction in packed snow and can be downright terrifying in icy conditions. I ran them for 1 winter and had at least two, if not 3 really close calls one of which involved doing a 180 on packed icy-snow conditions and crashing into a snow bank after getting some rear end wobble that I could not correct. After that initial winter, I got some dedicated winter tires, though I do still use the Evolutions May-Oct and will probably buy another set of them in the next year or so. I have seen people add after-market siping for better performance in the winter, but you'll void any warranty and you still are giving up an amount of surface contact that you need on ice with such big lugs.
Like all Mud tires, they are loud on the highway and gas mileage will likely be impacted vs. AT tires as Mts are heavier. That doesn't bother me, but I also live 4 hours from the nearest interstate so seldom drive faster than 65 and I'm driving rough roads most weekends in the summer. I'd say that, practically speaking, to justify MTs, you need to spend a good amount of time on rough roads and not a lot of time on the interstate and then, depending where you live, I would consider their performance in winter months. they do have one line of stud holes, which you can add at purchase. I don't have studs on mine so I can't comment how that may affect performance on ice. I have had studded tires in the past, but this is just a single row of studs. Where I live, you can have studs year around, but, for example, if I drive across the border into New Mexico, you can't have studded tires between May and Oct. So, that could be a wash.
If money were no object, I would have a pair of MT tires, AT tires, Touring Tires and Winter tires all mounted up and ready to swap out at any time. MT tires are a speciality tire for certain conditions much like a winter tire is, so I don't expect them to be practical for most people unless you just want the big lug look.