If you're anything like me JB you'll HAVE to get on any coaster you see. I quite enjoyed Manhattan Express (don't remember it costing a tenner tho), it offers another perspective on the strip and does contain one fairly unusual element.
Unfortunately I can't comment on the merits of Speed as it was down the entire time we were in Vegas. The tower sure does look pretty though.
Besides, the $10 spent on Manhattan Express would have to be better than the 5 mins that would buy you at one of the 700,000 poker machines scattered around the place.......