I played a lot of Dynamo before they went to the brown top. I thought the tables right before the brown top were the best Dynamo ever made. The brown top was one of the reasons I switched to Tornado.
Like Ed said...Save your money.
If you're buying it to collect or for the kids, go for it if it's cheap. But if you're buying it to help your Tornado game, don't. The stroke on the pull is entirely different than Tornado and I don't think it would help your Tornado game (unless your a beginner). I don't shoot the rollover (I'm old) so I can't advise you on that.