i dont' know about that jay, if u had different tyres on the back i think it will effect it to an extent ... i mean consider when the hicas kicks in and u want to power ur way through the corner ... now if one tyre has more tread than the other the it will gripp more than the other which means some sideways actions depending on how happy u are with the right foot ... so i think it definitely effects the ride ... however i think that there isn't much difference in handlin when the tyres are the same for the backs and same for the fronts .. i dont' think it matters if the front and backs are different ... eg people with wider wheels at the back ...