In 20 years, I've seen SpaceX start from scratch and develop and launch the Falcon 1, Falcon 9, and Falcon Heavy, and nail propulsive landings on Earth.

Since it's members joined forces to form ULA 15 years ago, I've watched them launch the same machines they've been using since 2002.

I have a lot more faith that SpaceX will launch something new than that ULA will get anything done.