The 2-stroke 49cc scooters are super polluters. Even if you don't care that all that crap is going into the air/environment, you might get the nice light-headed feeling I used to get on my Kymco People. Basically all the exhaust would come around the bike and back near your face when you stopped. Yummy! They stopped making the 2-strokes a few years ago and replaced them with 4-strokes that are a little cleaner but not as fast.
Don't know if I'd want to ride across PDX's steel platform bridges on a wee scooter either but plenty of people do it all the time...
Ducati Monster 695?