Okay, my M5 won't be in for a couple of months more so here's a win and a loss from my last hot car, a '91 300ZX turbo. K&N, chip, exhaust. Probably made 400 hp.
I used to get challenged by Moostang GT's all the time, but one I enjoyed the most was coming home from work one day following a GT convertible at 70-80 mph for many miles on 287 east. (road details provided for those that know the Westchester, NY area and can relate). The GT had dealer plates. We both had come from Rockland County and since the owner of a Ford Dealer in Rockland lives in my home town, I think I was following the owner of the dealer. Anyway, we both get on 684 North, I'm about three car lengths back and we are at 60 mph. I see that telltale puff of smoke from his pipes so I know he's pegged it, but I had been waiting in third gear with the turbos spooled. Stood on it and went around him like he was standing still. Absolutely humiliated him. Nothing less.
Another time, late at night , coming off the TZ Bridge into Rockland Co. on 87 North (I'll call it "the 87" to make you Calif. guys feel at home). I had caught up with a nice bike at about 70-80 mph. I don't know bikes that well, so I couldn't tell you what it was, but... He gives me the nod and off we go. Over the years with lots of kills I had grown overconfident - I didn't even downshift from 5th. Just nailed it. Off we go together, pretty much neck in neck right up to about 110, maybe. I'm thinking "wow, this Z is awesome, bikes aren't all they're cracked up to be." Then all of a sudden this guy downshifts, I hear the engine scream and he takes off like a bullet. I mean a freakin' bullet. I swear to you that my jaw dropped open. Never saw anything like it. One big slice of Humble Pie. That's what I ate that night. Loved that Z, though.