In case it's of use to anyone, I've got one of these docks and it seems to work pretty well. The original version had a few flaws, which seem to have been corrected.

With my MB Pro, there are no driver installs, and all the ports seem to work perfectly. The dock supplies charging power on the USB ports even when the computer's not attached, making it a useful mobile device charger.

The only downside is that it's pretty expensive.