Just got mine today and have been playing - flashed my Hitachi without any problems...
It's definately slower that doing it via SATA, but it works, and it means (with an external power supply for the DVD) that you can use a laptop, which is handy; shame it can't power the DVD from the USB too, but that would be asking too much I think.
One thing I don't like is the super bright blue led cluster on the Xecuter v2 connection kit - I don't need to be blinded every time I connect the damn thing, thanks all the same. The Mode B and Eject switches are a bit weird too, the are puch and lock switches rather than push to connect - so they stay down and down activate till you press them a second time to release them, which is just bizarre.
Anyway, it's a nice little unit and you get all the cables - as I say, it's a shame you still need to use the connection kit too (to change to mode b, eject etc).
One great thing is it now has a power switch on the connectivity kit, so you can flash MS28 version of the Sammy without yanking the power cable out for 10 seconds... now if only you could use USB to flash the Sammy too, that would be really useful. Maybe next release?