I got a hard set from costco too. It was similar to this one
http://www.costco.com/Samsonite-Silver-2-piece-Polycarbonate-Hardside-Spinner-Set.product.100116082.htmlI love the way it looks and how smooth it rolls with 50 lbs. I still have the set and love it but some pointers.
With a hard set you don't get outside pockets, it could get scratched. The one I got has 2 compartments on the inside. One that closes with a zipper and one that doesn't. It took some time for me to learn which side is down without all my objects flying out.
Also, for the smaller carry on, you should be fine flying domestic. It will fit on top despite what people tell you. I don't know about international flights. I've read reviews of people having to check in their carry on.
You also have to add a string or some kind of tag to know it is your bag. I thought my bag was so cool and different. Low and behold, someone on a recent flight had the same one as me.
Overall, I love my Samsonite and lifetime warranty at Costco