I just sold my Bally Black Pyramid that i mentioned earlier in this thread, had it for about 3 yrs. Sold it to a guy who was after his first pin, just something fun to play that didn't cost the earth and he took a liking to BP when i let him play it and told him that i had been thinking of selling it with an unrestored p/f but fully working.
Although i DID like BP as a player and had intended on doing its p/f up one day, it didn't fit in with the rest of my collection visually, and i really didn't like the sounds that much), and it didn't fit with my collection in the sense that the bulk of my collection are games i played a LOT back in the day (only played once or twice). It was one that i basically got on a whim, so when opportunity knocked, out it went! I have my eye on a couple of other games that will replace it when the time is right
Also i had my Abracadabra and Klondike for over 20 yrs before i sold them so those two held the record for longest kept machines that i've sold.