Most of my reading seems to sugest that those with a slice are better off going with a Draw biased driver rather then an off set. (I do not have a slice problem so I maybe mistaken)
Anyway I swung a club with an off set and can tell you there is no way I could ever get used to lining the club up at address. It is I am sure a personal preference and it appears that such
clubs help some people, but I would not put down the money they want for a new driver unless I tested it and was sure it was going to work.
Bob