I've had good success keeping CPU and memory usage down with decent load times with my Dreampress hosting site through Varnish, some .htaccess expires, Pagespeed, and the Memcached object drop-in for Wordpress.
I'd like to get back to using W3TC for an upcoming event that will result in high load. On shared hosting previously I found W3TC using disk caching to be worse than useful. I've XCache checked off now with Dreampress. When I try to use Opcode: Xcache in W3TC, I receive an error.
Any tips to getting XCache up and running on Dreampress? Is XCache object caching going to be superior to Memcached?