It seems just about every movie uses a Cherry MX for keyboards, even if that's not what's pictured in the actual film. Sure, I can tell buckling spring, from Cherry from Topre, but I would never expect to be able to tell the sound difference between the Cherrys (blue excepted, of course). Modding Cherrys with O-rings would throw that off too - it's usually the distinctive bottoming out sound that tells me Cherry. In my limited-compared-to-some experience with Topre, it sounds pretty distinct too.