I am considering buying an iPod Touch. I see I can get a refurb one from the Apple Store for around $245. But, that doesn't include the software update, so that would put the price up to $265. I can get a brand new one off of eBay for $220 + $20 for the software update. Should I consider one off of eBay? If you need warranty service from Apple, do you have to have the original receipt or just the serial number?