the whole point of the tool in the first place wasthat it was supposed to save you time...
neer mind arches and the like, would you really go ot and pay 40 quid for a tool to cut one arch every 6 months when you can do just as good if not a better job with a saw and a surform?
waste of money imo, i GAVE mine to a chippie mate who does a fair bit of glass replacement for cutting laminated glass (you need to score both sides before you snap it) thought it might have its uses...
far as i know its buried in the bck of his garage somewhere...
nice idea, as far as 'tools' go youd be better off with a 12v circular saw!