I had previously seen both at the International Motorcycle show last December, but I I happened to be near a BMW shop today, so I stopped in to see them. The production models are so much nicer in fit and finish than the ones I saw at the show. There is no mistaking the BMW DNA in these scooters. The way the electronic windscreen works on the GT is like something you'd expect from BMW, and it makes my Burgman electonic windscreen seem like second string. The display has lots of useful info, the heated seat and grip controls are convenient.
The Sport model sits a little lower to the floor, has black powder coated wheels, stainless inserts in the foot area, and just looks more like an elongated sport bike. I had thought the GT might outsell the Sport, but having seen the sport in person, I may have been wrong on that assumption. All three bikes the dealer received were already sold.
I am hoping to test ride one at another dealer soon. Very nice scooters.