You probably won't get a lot of first hand reports on the Mu, because that frame is new this year. There is one thread on the Dahon Forum, though, from their most regular poster, who has a prototype Mu XL (that's the hub gear commuter model). You can find it here. There have also been some threads there from Jetstream owners, both the P8 and XP versions if I recall.

You can also look on the Folding Society's Dahon page. There is a detailed review of a Jetstream XP, and also one on a highly modified Jetstream P8. Hope that helps.