Yeah, I don't like the antenna either.
I'm getting pretty anxious for a new i-mate WM2003SE ROM. I hope they add Voice Tag dialing support so you can use the Bluetooth Headset to initiate a call. It sounds like the H6300 does not have that capability, although it does have the ability to send system audio to the Bluetooth headset.
It looks like the MMS app on the H6300 is integrated with Inbox too, but the New MMS dialog looks just like the Arcsoft MMS Composer dialog for creating MMS messages. I wonder if there's a new version of MMS composer that integrates fully with the Pocket PC Inbox! Hopefully we'll get that on the XDA II soon too!