Hi, I've recently had both the basICCaliCube and basICColor Gray Card to have a look at.
Both very useful (I'd used assorted bits of 'grey' card before for WB assistance) but I've found the cube with its built in light trap and chrome ball (to show up specular reflection) really useful when doing product shots in factories and other places with less than optimal lighting and I don't want to go to the trouble of making a custom camera profile.
If anyone is interested I've written up some more info at:
www.northlight-images.co.uk/reviews/photography/grey_card.html
