I used to work with a guy who used the original Model M that he had with the PC he was given in the late 80s/early 90s. It's survived multiple coffee spills an

I used to work with a guy who used the original Model M that he had with the PC he was given in the late 80s/early 90s. It's survived multiple coffee spills and at least one case where it was repeatedly picked up and bashed against the desk out of frustration (both key-side down and up). You'll almost certainly get that 20 years. If you want to restore the keys -- and to be clear, I can't honestly recommend this approach -- but I used to bathe my Northgate Omnikey and clean it with dish soap, followed by a trip to the oven on the equivalent of a "keep warm" setting for a half-day. I was surprised that a lot of the discoloration on the keys wasn't the usual plastic oxidation but was from the oil and grime on my fingertips. It always came out shining and like-new -- partly because whatever they did to print the letters on the keys was very resistant to being worn off. I did it about once every 2 years during the decade and a half that I owned it and it was sold at an estate sale in perfect working condition 15 years after that. At least one person mentioned using a dishwasher. I've never tried it, and would never do that to a modern keyboard, but I'd imagine the effects would be similar with a whole lot less effort.