I have always wanted a Wimshurst Machine and was able to afford the one on Engine DIY. After waiting a week for it to arrive, it was mostly assembled. A few tightening adjustments and it was ready to go. I've been playing, well experimenting, with it daily. I managed to get some 4 inch sparks with it while turning the discs rapidly enough. However, 2-2.5 inches is the average. You can also get some nice corona (see my video in darkness).
Quality is what you expect for this price range. The sectors are "painted" on and are already rubbing off, but I can adjust the brushes to wear out other portions. I wish that the site would sell replacement brushes, belts, and discs as I know I'll be using this a lot.