I currently have 245/75/16 on mine and they do not rub at all. If you look the 31x10.5x15, they are aproximately 3/4" wider with pretty well the same diameter (245 d=30.47" w=9.76" compared to 31 d=30.51 and w= 10.55")
I think it would be safe to say there would be minimal rub. I had rims with 1" less back space before with the same tires and had slight rub on sharp turns and these would be like having a difference of not even 1/2" back space on your rims.
As far as ride. They are rougher as they are a pretty heavy duty tire, but I think they are an awesome all around tire that doesn't seem to wear too quick. One not, don't be shy in rotating, as they are an agressive tread and will chop/scallop quicker and will become louder (raoring) when this happens. This is from experiance with the first set. I have been pretty religious in rotating these at 5000 miles and haven't seen this happen yet (have about 15000 miles on them now)
Hope this helps,
Denis