[tasaro]

The best choice is the one that provides you and your users the lowest latency: http://www.linode.com/speedtest/

On a side note, all facilities (and not just Linode's) will experience issues from time to time. You want to evaluate the manner in which it was resolved and the frequency. Don't move because of one outage in the last several years and degrade the experience for your customers. If an outage is going to damage your business then you should investigate high availability and/or quick deployment strategies.

All of that being said, if your users are mostly US based you probably won't notice the latency between any of the US based locations.