Styling wise I love the Vespa GTS 300. However I am not sure how this scooter will do on the highway's around here. From where I live its pretty much impossible to get anywhere without having to travel a very busy highway with some steep inclines (101, 280, 92).
I can comment on the Kymco...
I've done all of these roads with my People 250 - it kept up with smoothly flowing traffic with a bit of power to spare. Just don't expect to be able to pass with authority... On the flat stretches, it moves comfortably along with the pace of traffic in all but the fast lane.
I've also tested a Downtown (same engine/approx. weight as the People 300) - it certainly has more power at the higher speeds, but didn't have the impression that passing acceleration would be greatly improved on steep uphill grades at lower speeds (i.e. think about moving into the fast lane and accelerating quickly to get around a truck going up at 35mph in the slow lane). But for flat stretches, it'd be fine. In the end I decided to stick with my old People though based on...1) Found out the sales guy wasn't being completely honest (or had a different interpretation of the question "Was this bike ever dropped?"), and that the seat was too low (probably could be altered to fit at an auto upholstry shop).
Also I wander about the stability and ride comfort (bad roads and back) in relation to the suspension and wheel size).
The Kymco's I've ridden (People 250, Downtown 300, and Super 8 150) all have had firm suspensions. But I'd consider a good thing as it does seem well-planted. My only concern has been with the People's geometry that some how doesn't seem quite "linear" to me when cornering. In other words, there's a range in cornering where the steering responsiveness gets a bit too touchy for my likings. Don't know if that's still a characteristic in the GT300i, and it'd be one of the reasons why I'd insist on a test drive of the People GT300 before buying one.
Hope at least some of this is useful info. for you.
Cheers,
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