You have it and it's working for you?
What could you sell it for, and what would you replace it with? I suspect the resale on it wouldn't be great, people will assume it's a bad one if you're selling it. If it's working for you it's likely that it's worth more to you than you can sell it for. You know it's working and it's history, someone buying it doesn't.
However, if you can find a buyer at a good price, and change to something else without putting much money into it, then it would manage some risk for you.