Am just finishing set up of multi site network

Hi

Am just finishing set up of multi site network and concerned at what appears to be quite slow times for site to load pages (this is with no traffic load yet!)

Summary of set up;

1. 8 sites in network
2. 15 or so plug ins - have tried to keep to minimum as needed.
3. Hostgator VPS level 3 install = 1.13GHz CPU, 768 MB RAM
4. WP Super Cache activated

Have seen articles about Gzip compression
eg. http://diythemes.com/thesis/improve-website-pagespeed/#gzip

a. Gzip plugins are available but note that WP Super Cache state that they cannot be used with Super Cache.

b. Also read that some users are adding these codes to .htaccess file;

#Begin gzip and deflate
<IfModule mod_deflate.c>
AddOutputFilterByType DEFLATE text/html text/css application/x-javascript text/plain text/xml image/x-icon
</IfModule>

server {
gzip on;
gzip_types text/html text/css application/x-javascript text/plain text/xml image/x-icon;
}

Are you able to comment / advise on this as it is bot clear from what I have read if this action is compatible with existing caching setup like WP Super Cache .

Many thanks,
Paul