only thing I would worry about with running the square tire bryan is if you have to lay down the
bike little when going into a corner hard or even slow. you will get to a point where the rear tire will want to wash out from underneath you with out having any side wall traction. one thing I do like about both tires they are built with a lot of side wall support. i'm sure it's got to do with being on a piece of heavy equipment(snowblower). even though they are not rated for speed I still think they can handle your speed's. but you could get little vibration from that one tire you have and that's probably because of the tire design. I believe your shinko tires are speed rate 50-60 mph and that's still a good tire to have. snow hogs would be interesting tire to test out.