clubdot,
RV-Sitebuilder does work well with changing servers.
Basically, it depends on how it is transferred, but if you transfer using cPanel and the new host has the sitebuilder available, it will copy over no worries.
You may need to restore the database though on transfer (which is just the click of a button in the sitebuilder - very easy) upon some transfers.
Alternatively, you can backup the site project from the sitebuilder and restore the backup on the new service.
The site itself however, if created in RV Sitebuilder and your moving to a host that doesn't use it....well, I cannot answer that one, but I would be more inclined to suggest against it.
Regards,
Dale Evans
Manager