Review (5/5): Got the green one
My old Oral-B's battery gave up the ghost. I think I had it for about 10 years. I still had several unused brush heads left over, and was a bit concerned if they would fit on the green model (some reviews here confirmed they would though). The smaller regular heads do fit. I assume the brushing action with the smaller head is the same as the blue one's, but not sure.
I find the green model's brush head too large. Maybe I'll get used to it. I prefer substituting the small head because it is easier to concentrate on one tooth or in between just two teeth. The larger brush pretty much covers the entire side of my mouth, so might be good if I'm in a hurry.
For all you drooler reviewers out there; tilt your head back while brushing.
Another thing to try is brushing with mouthwash, it gets my teeth cleaner more quickly than toothpaste. Plain baking soda works great too. I'll sometimes follow up with toothpaste or brushing with the anti-cavity rinse for the flouride.
The Oral-B Vitality seems to work just as good as my old trusty oral-b, and cheaper to boot. I wish more products were as well made and economical as this.