Sell or keep N900

I recently got a replacement N900 unit as the previous one was broken. With it being sealed, I have been contemplating selling it and using the money to buy a N9. However after looking at prices (ebay mainly), I'm not likely to get much more than £150 for it.

Would it be worth selling it for this much? I don't need the extra money and I could use it as a sat nav and music player for the car as the USB port is unlikely to break there. That said, the extra money would cover about a third of the cost of the N9.