I have several pieces of this luggage collection and for the most part, have been pleased with the set.  However, I had received the carry-on spinner briefcase (as a gift) and due to it's size, I hoped to use it as a carry-on for clothing & personal items.  Well, no big surprise, the style of the briefcase (lots of sections & compartments) was well suited for a laptop, notebooks, etc. but not ideal for clothing, shoes, toiletries, etc.  So I ordered this under seat bag and I'm glad I did. Although it is slightly smaller than the rolling briefcase, it holds more of the items that I need to pack.  I like the external zippered pockets - they offer easy access to some items without opening the main compartment.  The quality is good, it rolls smoothly and so far, although some reviewers complained about the handle, it seems to be sturdy enough for my usage.  I supppose the choice of carry-on bags depends on what you intend to carry but this bag works well for me.