Samsonite Oyster. The older ones seem better than the new, or it may just be that the Japanese ones are/were made by the same company that makes every other brand, too. I think a nice fat strap around a case improves the case life remarkably. I had one expensive 4-wheeled case that looked fine on delivery, but when I took the strap off the two halves went "sproing" and deformed never to be closed again. The closest I've seen to an Oyster recently is some Brit thing, I can't remember the name, which has also proved very durable.
But now weights seem to both reduced and enforced, I'm looking for something much lighter. My existing case is nearly 7 kg, which leaves only 11 to 23 kg for the essentials of life.