Memcached and eAccelerator

[MikeF]

is it safe to disable suphp if it's currently enabled?

Seriously consider XCache as opposed to memcache. Memcache is best used with multiple servers. There is the idea of using nginx but this is best when using Lighthttp. The other option is to find a webhost that supports LiteSpeed and just run it with XCache, as you will notice a massive improvement in load times overall. It is important to note that LiteSpeed will piggy back onto an existing apache configuration, especially if you are using WHM and Easyapache.