I have been a die hard BFG KM2 fan since they came out, and KM's before that, and M/T's before that. I have owned about 15 different sets of BFG M/T's over the years and have had three sets on my Tundra over the past few years. Up until a few months ago, I was adamant that the KM2's were the best all-around tire choice out there. My only major complaint was how easy it is to cut side walls, I have personally killed four KM2's and have seen numerous sidewall failures on various vehicles, some could be expected, some totally unjust.
I can say with 120% confidence that even if the Hankook sidewall strength ends up being equal to the KM2's, they are hands down better in every aspect for me on my vehicle. Now I'm also willing to bet that the Hankooks sidewalls are substantially tougher than the KM2's.
That's not to say that the KM2's are junk tires, but I think they are way over priced and the sidewalls suck......and yes I have had this discussion with the man that designed the KM2's on several occasions
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On a lighter vehicle, the KM2's would be fine, but I think you would be mildly surprised by the Hankook (both on & off road). The Toyo M/T's were my all around favorite tire out there, but I simply can not get past the weight of them. The Hankooks are better on the road than both the KM2's and Toyo's on my truck. On a lighter vehicle I imagine the Hankooks would ride rougher than the KM2's due to the E-rating though.
So bottom line is that you have to find a tire that matches well to
your intended use and
your specific vehicle. The KM2's, Toyo's, Hankooks, Coopers, etc are all good tires for certain vehicles. It's just like with the MT/R's w/ Kevlar.....I can say that they were the worst tires that I ever rode on, in every department, and I will never own another set of Goodyears, but there's plenty of people that will report just the opposite.
I'm glad to hear that others are having good results with Hankooks.....I was worried that I was losing my mind. I'll say that when I first started reading the rave reviews about them from the FJ crowd I was slightly more than skeptical, but my initial skepticism has thankfully been proven incorrect.