After two days of riding, the answer is NO, I won't miss the Blur at all with one exception: the brakes. The Blur is a brilliant scooter, but now I understand what the premium price of the Vespa is really all about. Worth every penny. The GT feels like about 150% of the power of the Blur, but about 80% of the brakes. I think some stickier pads are in my future.
That one thing aside, I absolutely LOVE this scooter. My biggest qualm with the Blur was the ergonomics - I simply didn't fit right on the thing. It's a great scooter if you're < 6' tall, but for my 6' 4" frame, it was just too compact. The Vespa (like my P200E) fits me great and I've got the whole length of the seat to vary my riding position. I'll have to break in different parts of my butt, but it's all good.
The GT, in my opinion, is exactly what a scooter should be. The Blur was leaning a bit far toward sport motorcycle. Between the 12" wheels, the low center of gravity, and (oh my goodness!) the looks, the GT is simply the pinnacle of what a twist-and-go motor scooter ought to be. Accept no substitutes. The power is so effortless and smooth and I swear I could just feel its aviator lineage. Grasping the handlebars and rolling on the throttle, I half expected it to take flight at any moment like a brand new Spitfire...but Italian.
Photos at:
http://www.flickr.com/photos/nathaniels/sets/72157608183686642/