I thought Sports Night was an amazing show, probably one of the best ever (after Whedon's trinity), but not because of Peter Krause, although he was good in it. It's wonderfully executed by a tight ensemble cast, the writing is superb beyond words ("How much do you love me now?" being one particularly memorable highlight), the dialog is deft and realistic, the chemistry is palpable...I could go on and on. I need to get that back from the person I lent it to and watch it again.
I still haven't seen Six Feet Under.