apt-get vs apt-rpm vs rpms

Folks, Despite using SUSE off and on for some years the first I knew of apt-get and apt-rpm was from comments in some mails in this list. I've just read the FAQs for both and I'll certainly try them out some time soon. First 'tho I'd appreciate some comment/reports of experience to help me with the best (and safest!) way to use either. TIA, Colin