i don't think there's a right or wrong answer here ...
on the left, there's receiver only
in the middle, receiver with amp
on the right, there's pre-pro amp
the advantages of the "left" is all-in-one convenience, price, features
the advantages of the "right" is that you can upgrade the pre-pro only and save the amp, there's normally more power in a separate amp than a receiver, some people say the separates sound better, brand name recognition, they say the separates are built "better" because they are not mass produced.
me, I'm in the middle, I like the new features, but I also like more power ... so I went with a receiver and amp combo.