WTB: T510/T520

[CoolRunnings]

Looking for the best bang-for-the-buck T510 or T520. Priorities (in order of importance):
1. Warranty.
2. Cosmetic condition.
3. Processor speed.
4. Hard drive size.
5. Screen type/resolution.

I'm shooting for the sub-$550 market if at all possible. I'm also interested in a dock for it. Looking to buy this week asap. PM me with what you have!