Be careful when buying Mach 3 turbo blades on ebay. Many of the blades for sale are not Gillette quality and do not provide a good shave. They look like and are packaged in the same way but are clearly seconds or god copies. The only way to make sure that you get Gillette blades is to stump up full price in a high street store!
Several of my friends and myself have been dissappointed with blades purchased through sellers on Ebay.