dude...come on, those models are sweet!!! my wallet twitches every time i see them
as for being useful...hmmm....now to what use could i put a pair of somethings that could potentially move upto 24" in a single turn and hit with d6+1 s5 attacks each?
i was thinking about it the other day and i recon they would make a good unit to set up on a refused flank. they could slow down half the opposing army for a few turns while the rest of your lads get in and kill stuff. best bet would be 2 units of 2 i think for vp reasons.