I had the lightweight flywheel put on before I even picked up my Viper with the intentions of putting on the Roe Supercharger when they would finally come out. (Bill Pemberton's advice to put on the lightweight flywheel.)
It gives me an almost instant match of RPMs for down or up shifting. I find it very easy to drive my Viper that way. This is the 1st manual shift car that I've ever owned. I've never driven my Viper without the lightweight flywheel, since I had it installed before I even flew out to Blair, Nebraska to pick it up and drive it home.