I think Utopia is better than these two, though I agree that they essentially form a three parter. I think, when you look over Masters, Delgado increasingly looks like the odd one out. Simm and Gomez's performances both seem to me to take the same starting point - mercurial, unpredictable, unstable - and I suspect that interpretation has its roots in Ainley's mad cackling though he was less likely to arbitrarily kill someone, and considerably less likely to play with them first. But I preferred a Master the Doctor could have a sensible conversation with, and I don't think he can do that with the modern ones.