I resurrected myself here (first time in 3+ years) just to reply to this post. I read it while debating on getting the Essential Sleeve. I ended up purchasing one and wanted to share some content.
I am a clean freak and was concerned about having to gate check a Poly bag to have it maybe get scratched up as well as deal with waiting for it during tight connections, etc.
Was quite happy to see it fits in a CRJ 200 without issue. I also use a suitcase cover to try to help keep it from getting scratched (Rimowa does not make one for this bag so I am using a mis-fitting third party cover)
Zipper pouch works well but not fantastic smooth zipper wise. They take space from the internals of the bag to give that pouch enough room to put things in there like a wallet, etc. without it bulging out.
Bag rolls really well. I moved to this from a Briggs and Riley Rolling Briefcase and then an Away Rolling Briefcase so I have not had a higher end rolling briefcase before.
Hope this helps and more than happy to answer what questions I can about this bag.
Rimowa Essential Sleeve in a CRJ 200