My hero's, my dreams, and my future lie in Yankee Stadium and they can't take that from me.
As long as I'm still able to have a hit on the radio and sell a few albums and some tickets, I don't see that it would be worth retiring.
I wouldn't say one is easier or more difficult, but when you're inside a costume and a mask, you have to endure heat - and, often, difficulty seeing. The vision is not very good in a mask. And you have to cope with that, as well as trying to think about this character.