I have 6 that I use now and again with the oil finish, I don't use them a lot and they hang, not stored in a case. I never have done anything to them, would say they were done 5-8 years ago. One is about 35 years old. Same original finish. If you use them every day you may have to do a bit of maintenance every now and then. I like the wood look and feel more so than normal finishes. Guess how you treat and use them would be the big factor.
Steve