experience with Dell Powerconnect switches

we're a non-profit that is slowly replacing our aging flat 10base networks at our campuses around the country. We are committed to Cisco at the mdf but to reduce the expense, i'm considering Dell (we buy our PCs from them).
I've heard a couple of anecdotal stories of problems and i in fact have one with a gig switch from Dell that won't see the fiber module and i've seen some posts with the same problem.
any opinions?