My Weekender Convertible Junior bag arrived today. Someone mentioned it in an earlier thread, and, after looking at their website, I liked it so I ordered one.
So far it looks like everything they said it is (cinch straps, sternum strap, waist belt). It has YKK zippers, which I feel is a plus, although, if you don't pack it to bulging, you shouldn't put too much stress on the zippers. It feels awfully light; I haven't been to the Post Office yet to weigh it but it might be lighter than advertised.
If it weighs what they said it does, it's 14 oz heavier than my Essential Carryon bag, but the cinch and sternum straps and waist belt, which I have been thinking of adding to my EC bag, would weigh something. AND, it doesn't have an obnoxious label on the outside (well, my bag was from Outdoor Product, before Campmor took over and added that label).
It's $20 more than the ES bag, but by the time I paid someone to add cinch straps and a sternum strap (I could probably do without the waist strap belt since I pack really light), the cost would be about the same.