I thought I got a good deal at 5500USD out the door! 5100 is a GREAT deal! Especially with gas pushing $4/gal!
I'd feel giddy pulling the trigger at that price.
I think with the B400, it all comes down to styling, the performance is very similar. I had a B650, it was great but a little enormous.
My wife & kidniks LOVE the passanger accomodations on teh DT300 - Especailly now, with the Shad SH33 topbox with the backrest. Heck, my wife wouldn't even ride on my GSX650F... She happily hops on the scoot.