I sometimes use PubMed, but our school uses MDConsult, and EBSCOhost through Universitiy Medical Center of Southern Nevada. Our school also has a subscription to Ovid http://www.ovid.com/site/index.jsp
which I use regularly to search for literature. Have you checked what other databases your library has subscriptions to? I think you guys have access to MD Consult, and Wiley interscience database, although that only covers journals published by Wiley. Sometimes I have a hard time getting access to full text articles, especially if they are older articles (we lack a large academic medical library), so I have to pick them up when I get back to California, at UCLA or UCI.
It depends on the assignment. I prefer Micromedix and Clinical Pharmacogy for drug info. They sometimes make us use the PDR, though. For journals, I use Pub Med because I used it as an undergrad and got accustomed to using it.