I was looking for a way for one person to manage the luggage of two people on extended trips. This seems to be a great solution for us. We didn't need or want the really big suitcases, but the two 24" size, or that plus one carry-on should work well for us.
I'm not a fan of the clamshell split open mode that all the hard-sided suitcases use these days; I think I would have preferred the older soft-sided version (though occasionally looking out an airplane window and seeing bags sitting in the rain on the tarmac can make hard sides seem better).
It would be nice if the pull strap had some way of storing external to the bags; that would be more useful than the gimmicky water bottle holder.
All in, I'm quite happy with the purchase, and thankful to the acquaintance who revealed the existence of these nifty bags to me.