I don't know. I have the original suspension and some of the higher humps in carparks and so on are already a problem. I would say be careful........ But it would probably handle even better than ever! :P
I have an RS200. It's been running on premium unleaded 98 fuel with no problems. Have yet try an octane booster (hmmmmm..) Was told by the dealer it needs at least 95 octane. Hope this helps.