Ipod touch Replacement Question

I've read somewhere that if you already had 5+ replacements and still have a defective one, they're suppose to give you a brand new one (sealed) not a refurb? Is this true?

Another one, I sent my ipod for replacement, and they said replacement will take around 3-4 weeks but my warranty will be expired next week. So if I received the replacement unit, there is no more warranty? or will it be extended? Thanks!