Re: Create Space vs KDP Print - I've noticed some differences. I just finished examining a KDP proof and comparing it to a Create Space proof (same work, text correction, no changes to the cover).
The KDP (snail mail) packaging is an envelope w/one interior layer of adhered bubble wrap. The former CS packaging was stiff, snug-fit corrugated cardboard that protected the book quite well. The KDP doesn't do as well; one corner of the book had its pages bent/crumpled (dropped?).
The ISBN does not appear on the bar code of the KDP proof; it does appear on the bar code of the CS proof.
The CS proof was boldly marked PROOF on the final interior page; the cover, to include the spine and back cover, was clear of any PROOF markings.
That is not the case with the KDP proof. A semi-opaque band about 1/2" - 14mm in width, located about three-quarters up from the bottom edge of the cover, runs horizontally across the front cover, the spine, and the back cover, bearing the mantra "Not for Resale". This band obscures anything beneath it, including text (e.g., blurbs, etc.), making it difficult to proof the entire cover.
The interior text of both CS and KDP proofs are acceptable; changes/corrections are as intended.
Maybe I'm a little picky; but, I'm not a fan of the KDP packaging, nor the "Not for Resale" banner obscuring aspects of the cover.