I had a set of the M55's on my 2003 4Runner and wasn't that happy with them. Not that they where a bad tire but for that rig they where just too heavy of a tire. I ran them a lot on gravel since that was my hunting rig and drove it to Wyoming 3 times to hunt antelope. On one trip it snowed then melted and as everyone knows the roads turn to snot but I was really disappointed on how they performed in the mud, and as I recall they didn't do great in the snow either since they are a super hard tire. They did seem to last but I doubt I'd ever get another set unless I was really needing them for a specific off road need.
I now have a 2011 4Runner and just put on my 2nd set of "E' rated Goodyear DuraTracs - they are stock size just the E rating. I ran the first set to about 44k and they still had a decent amount of tread but wanted to get a new set for this hunting season since I was expecting a trip to Wyoming and the old set was getting a bit worn.
I'm usually not a huge fan of Goodyear but the DuraTrac tires for me anyway have been great. Reasonable quite when on the road, pretty darn good when its wet and great in the snow and mud. I've run them in Eastern Oregon on some pretty nasty gravel roads and so far no issues with punctures. At least not with the "E" rated tires.
I think cost-wise they are about the same as any so might want to take a look at them.
