Yes I'm very familiar with these, I just never messed with the advance as usually we upgrade people to a pro billet type if they want that feature, especially with the vac being fixed. We have great luck with them for mild builds. I don't know how ebay guys sell them for $45 though. I think mine are 60. But at least you have a face to a name and a warranty. To each his own however. I know you bought yours years ago. I fully believe there are a few companies in China making these. Mine have always been nice distributors as your describe yours....but man we have seen some junk versions at swap meets. Ugly warped castings and such