I switched hosting provider within the last few months, I was running a VPS with unixshell in the states, but some of their transatlantic links dropped about ~20% of packets so it was slow for me.

Also for the resources I was given the cost was not worth it. My experience with plesk/virtuozzo is that it can be over subscribed. My new hosting company Byte mark give me a guaranteed amount of resources to my VPS a d so far the uptime has been good.

Bytemark uses linux KVM for their servers and have native IPv6 which is great, I also have twice the amount of ram and HD space.