Just stick to
Cyberwurx for your dedicated box. And then get
MAXCDN for caching and delivering data all over the world. I have a very busy network at Cyberwurx that was running 3.x load averages with my old host. Cyber got that down to .1x by properly tuning things up and then adding MaxCDN made it so no matter where you are in the world, it takes less than a second to load the page.
Did I mention 34/7/365 support that is always truly there? And extremely helpful!