It's not in any way cool or in any way a respected machine among the dirtbike crew and so it'll get laughed out of existance like the TW200 did, but for general commuting with the occassional bit of dirt I'd look at the Rieju Tango.
Sounds like Chinese monkeymetal but they're an established Spanish manufacturer. The new Gas Gas Pampera is a badge engineered 125 Tango, and one of their crossers is made by Gas Gas.
The Tangos look good, the 125s have Yam engines, they're narrow, not super tall, and they weigh next to nowt. I'd fancy the 250cc but the engine's an unknown quantity, not being from Yam, so I'd like to hear reliablity reports before going for it.
If the main use is on tarmac with the occassional bit of dirt, and you can cope with not looking harcore like you would on the metal posted above (although I think you can spec the more traditional phallic MX fender if you wish) they look just the ticket.

Vid of someone messing around on an mx course the 250:
http://www.youtube.com/watch?v=cEfz_EnWNtI