I was only able to properly test drive the 50cc as I haven't gotten a license yet. But my general reaction was: "WHEEEEEEEE!!!" It felt so much better than the vespas I've test-ridden. No matter what size vespa I tried, I felt very uncertain with steering, but the buddy just seemed so intuitive and smooth to me. Of course maybe it just seemed that way because I was already smitten!

And, the 125cc at least, seemed so easy to manage. That balance was great, it was easy to hold, easy to reach the ground, easy to push off the centerstand, easy to reach all the controls with my thumb. A really big factor was that it felt very easy to reach the brake levers. My hands are on the small side with short stubby fingers, so I find it a stretch to reach most brake levers. And the underseat storage looked huge in comparison to others.
Practical considerations aside, the deciding factor was that I fell in love with the Buddy!
I'm sorry to blather on, but I'm just so excited I could burst!