What school doesn't give it's students UpToDate access? Pharmacists always ask me to look stuff up for them in sites where they don't have institutional access. That said, I've never looked up drug class overview/comparisons on there, and have usually used Pharmacist's Letter for that purpose. What do you search? I just typed in ACE Inhibitor and got a bunch of articles about disease states where you would use one.
I also thought most class differences were kind of based off of what drug was used in what trial, ie just because enalapril reduced mortality in CONSENSUS, doesn't mean that lisinopril or ramipril would not similarly reduce mortality. I usually use class comparisons for formulary dose equivalence than indications though.