I was a huge Musk skeptic...until they landed that rocket back on the platform in the middle of the ocean. I decided to get a Tesla and best of all, buy the stock.
As for the Mars stuff, I don't agree with it. He's said that the only way for humans to survive is off-world, but we're not even close to being able to travel to distant planets, much less ones that can sustain human life. The money would be better spent improving conditions here. But hey, he's the genius.