I had the Costco. Used it on one trip and decided to get the Luggage Works and keep my Costco as a spare. Walking around on our ramp here, our cargo hold in the airplane, etc. That Costco special wouldn't have lasted a month. I can't remember how many severe knocks and slams my PNT has taken on the ramp, from curbs, etc... Thing's a bloody champ.
Not to create a debate on a roller bag, but my Costco has been through hell - everything you describe, plus being checked at the counter more times than I can count. Nothing is harder on a bag than when you check a bag. I know, I worked the ramp for 5 years, anyway my Costco is working great, when it does crap out, I will not have to ship or send it anywhere, it will never have to be repaired and I'll not need any sort of receipt. I'll just walk into any Costco and get a new one in about 5 minutes.
TravelPro and PNT may be great bags, I'm sure they are, but they're not $99 and my guess is the getting the thing repaired or replaced will take more than 5 minutes.