I like McDermott. I have a ton of respect for how he created a winning and togetherness culture. In a league where it's ultra difficult to stop offenses, he's been excellent overall at game planning and getting a lot out of individual players.
On the flip side, if I could choose, I'd much rather have an offensive guy. If coordinators come and go, your offense is always taken care of. IMO, offensive coaches seem much more aware of end of game strategy. McD is atrocious at time out usage and it shows up too much.