Reading the excellent blog entry on the ThinkOutside latest drivers for their Bluetooth keyboard (same as the Dell keyboard), it appears that it works well with simultaneous use of other BT devices.
From
http://www.pocketpcmag.com/blogs/ind...pb=1#more48 2
...
If not for the inner bugfixes/small improvements, it may be worth upgrading if you use Bluetooth a lot for other purposes; particularly, if you connect to the Internet via Bluetooth (via, for example, a GPRS phone). Disconnections have always been a major problem with BT connections when you type very fast on the TO SA keyboards or keep pressing the Backspace button continuously. This problem is likely to come up particularly when the keyboard wakes up from the power save mode. The problem is seemingly less common with the new version. I've only managed to bring down the GPRS connection twice with massive input / deletions / waiting for the keyboard to hybernate itself and then, wake it up by starting to enter text very fast. BT disconnections may have been a bit more common with previous versions.