My Stowaway XT broke recently, and I use it so frequently that I couldn't wait the month or two until the Bluetooth keyboard comes out. I was tempted, until four things occurred to me:
1) The devices are sitting right next to each other anyway, so I don't really get the big advantange (assuming I can make my iPAQ last the way I'm trying to, and not replace it for something with a different connector soon).
2) I'd have to tell the iPAQ to see the keyboard every time I used it, which is annoying, compared to just dropping it onto a peg.
3) Battery life would drop considerably.
4) I wouldn't be allowed to use it on planes, or shouldn't be according to the current take on radio devices, though the air-staff would probably be oblivious.
What really clinched it for me, though, is that ThinkOutside were having a half-off sale, making the XT $39, versus the $140 for the Bluetooth model.