Datacenters.W4's Plesk servers are located in rackspace.com's Texas facility, there has been no network downtime for 2 years.
Specific domains can be setup on nac.net CPanel servers, please note uptime isn't as good.
Rackspace servers: AMD 1.53 GHz with 1GB RAM.
Nac servers: P3 1.6 GHz with 1GB RAM.