If the host doesnt use a PHP accelerator (which IMHO it should for an ezpublish hosting deal but maybe that's just my opinion), that sounds about right. It's otherwise not all too bad either, I get about 0.2s on a dedicated box used only by myself and your box surely will be shared.
This is without a PHP-Accelerator as the hosting company runs PHP in CGI-Mode (very strange...). But 5 bucks for 12Gigs of eZp-driven Webspace is still a great deal though... :-)
As Gabriel said - you should be very happy with 0,5 sec. I also had some sites running on shared servers, just as you. But I NEVER got under 1,5 sec loadtime. But if they advertise as "ez hosts" they really should be using a accelerator ... my opinion anyway :)
Im now running a dedicated server with php-accelerator...
I could, but that would surely against the forum rules. But to tell you in advance: The are running <b>CGI</b> mode which requires some tweaking of eZ Publish to get all features up and running. e.g. the WebDAV-Server doesn't work in standard CGI setups.