I used to buy cheap bags when hauling stuff back from China. These were 26" bags that would last 3-4 trips, when loaded with 40-60 pounds of stuff. For $20 or so, I couldn't complain too much.
For longer term bags, I just buy the Costco Kirkland bags. Yes, they do wear out (handles or wheels, usually), but with free replacements, it's a no brainer. I carry 60-70 pounds in the 22" bag regularly. They last me 3-5 years, usually.
The smaller bag is $100. They've replaced it with a spinner version, but I haven't bought one yet. It's been a few years since I've replaced the 26" one. I'd guess it's $130-$140.