I say f/t all the way....Petco here sells Gourmet Rodent as well....they aren't the best quality IMO, but it's convenient, until I order online that is. Also, we are going to try the 'gas chamber' method for Smitty b/c he absolutely refuses f/t, so far anyway, I'm confindent that we'll be able to convert him eventually.
Also, depending on the snakes size, one prey item/once a week is preferred.
EDIT: Marla, the Petco here sells both Gourmet Rodent AND Mice on Ice.