I may be out of line on this, but just cautioning that I believe this auction was shilled. If that is what you are basing your offer off of I would just mention to be careful.
That being said if you are fully willing to part with $5,500 over this Mewtwo then I guess it validates the price and you are perfectly within reason to do so with your money. With the way these things have been climbing it may even be a good buy to snag one now at that price point. I would expect one to come out of the woodwork for you shortly with such a solid offer. Inb4 $20k next year. 
