The front engine on our plane was 250 past TBO when we bought it, and it was just starting to make metal, but we replaced it at that time, as part of the acquisition.
I will take exception to what GMAs said, about wearing it out. They will want the engine to be in one piece when you go to get another, so you don't want to run it until it completely fails. Also, it is more economical to purchase the Factory ReMan engine than having yours overhauled.
Even if you had a VAR crank, you're looking at <$2K difference between overhaul and ReMan. Obviously, if you have a non-VAR crank, the cost is substantially more.
So, a question.
If they get an engine in with a non-VAR crank, is it likely (possible) that they will use that crank in another engine? I was talking to a person with Lycoming powered plane, this AM. He was telling me that the crank in those are being replaced in the engines that are 300HP or greater, his, but the same crankshaft part number is found in the 260 HP engines. In theory, they could take that crankshaft out of his engine, and use it in a rebuild of a 260 HP engine. Also, he expects to be down somewhere between 1 - 10 months.