You may be right but I'm thinking I have a better chance selling it as new and unused than one thats used.Seems a bit silly to get rid when you've not even tried it yet. You won't be able to sell it on particularly easily.
You don't HAVE to undervolt it, but it can help. It's really easy to do and there are plenty of guides on Youtube.
Most people when I've googled it seem to say don't touch with a barge pole unless using multi cards or if you can only fit a small card in and almost everyone says if you do go with one you will almost definately need to undervolt.
If I was really experienced with these things and understood it fully then maybe it would be different now I've bought it but it feels like starting out with a problem and worry I really don't need.