I don't necessarily buy him as a serious actor. Mad Men was so well written that I think almost anyone could have been an effective Don Draper. My opinion is that he pulled off about 90% of that role based on his looks. (I think it worked overall because there were so many very talented actors surrounding him.)
That said, I love him as a comedic actor. His SNL appearances are delightful, and I'm always pleasantly surprised when he shows up in comedy shows and films.
This is exactly as reasonable as any recipe review I've ever read. Which is why I stopped reading recipe reviews.