Ian McKellen doesn't have to chose. He's also Magneto, so he's really kick-ass.

The last question I was asked was whether to have a shower or have to choose and follow my choice for the next question, which is this one. I AM Gandalf now.

Gandalf is actually a Maia, a powerful supernatural being that's basically an angel and that cannot be permanently killed. They serve higher beings but seem to have a heck of a lot of latitude in how they go about their lives. Sauron was also a Maia, for example.

Dumbledore's just some guy who couldn't come up with a better plan to stop Voldemort than deliberately getting killed while manipulating an annoying inept child into saving the day and getting all the credit.

Gandalf vs. 20 Gandalfs. Asses to you guys, I'm the only Gandalf here.