There is a 15x6x6 turf saver, and it would be fine on the asphalt. I love my snow hogs. There are some more aggressive tires called the xtrac, I think. If you're mostly on the street and around the lawn, go with turf savers. If you're on the trail at all, I'd go snow hogs. If you're only on the trail, I'd go xtrac. Just my opinion.
i recently got 2 rear tires swapped out as well. & I do like them , Called Kenda Super Turfs' their wider, and have a fair tread style for on & off road
i too filed down the rear caliper to fit my tire as well.