The only time I've been able to see him onstage was in his most recent Broadway outing, "The Father." I thought he was quite good - worthy of the Tony he received (though I probably would've given it to Mark Strong for "A View From the Bridge" if I had my pick).
Still, even though I haven't seen much of Langella's work, and even though I've liked what I've seen, I can definitely see him as someone with a tendency to chew the scenery. I'd even say he did a bit of that in Chicago 7.