I have Courant's Introduction to Calculus and Analysis and also have Spivak's Calculu's and Thommas-Finney Calculus with analytic Geometry, I'm finishing my precalculus studies, and I don't have much experience with calculus.
I want to become really good at math, and I want to know (Real) calculus, so I'd like to know if Courant is good for a first approach or should I start with Spivak?