I always turn full page caching on for all pages unless I'm using Miser, which is a different thing altogether. I generally also use gzip compression through the .htaccess file.

I highly recommend doing full page caching and gzip together and it should knock out any issues you have with site performance. If you'd like more info on how to do gzip compression certainly let me know and I'll describe it more thoroughly.

One caveat though is that it can be a pain to build or edit a site with full page caching. it's best to turn this off while you do this, but once the site is live you should turn it all on unless you have special circumstances.

Thanks - I agree (full page in all cases has been set)