You should be able to play with these in HS (or other programs as well), shouldn't you? The interface is done using objects (as far as I can tell). They have an example using vbscript and createobject (on the phidgets site). Can't you do this within an HS script as well?
I don't mean to downplay the girder interface, which I think is a good idea. Just trying to determine/point out the versatility of these phidgets.
Edit follows...
By the way, despite my emphasis of scripting above, I do think that for some applications of some of the phidgets devices you would want to use a plugin.