I have chosen this textbook for the undergraduate real analysis course I am teaching, and I think it is wonderful. Some notes:
The text layout is simple, clear, and concise.
The exercises vary in difficulty from testing a student's understanding of a definition to testing a student's understanding of difficult proofs.
Until the later chapters, the author has chosen to do everything in R. This diminishes the impact of some important results (e.g. the Bolzano–Weierstrass theorem), but overall makes concepts much simpler for students to understand.