well as far as my understanding 650 because it is comparable to a 26'' wheel, which is a standard mtb wheel and common on dj/park bikes. Manufacturers readily have 650 wheels also. I'm sure it probly drops the center of gravity as well but it doesn't look like the bottom bracket is raised.

and you know you want to be able to do this
http://www.youtube.com/watch?v=vpJMK...layer_embedded

so I say get a dj or park or street park