Did setting up APC help with the caching performance on your VPS? We are starting to look at wordpress for our blog, but want to make sure it can handle all the hits.
Cache preload should help. To my understanding it will preload the pages into Cache so that the web server process does not have to hit disk to serve the page.
You want to do anything you can to keep all of your pages in memory. Also make sure your vps has enough ram.
If you have enough ram to fit all the pages into memory and it is still slow to load, contact support to get moved to a faster server.
