"This doesn't necessarily apply to the carry-on sized TravelPros..."

Well, let me correct myself, it can apply to them also. One of the wheels essentially crumbled and left us with a loud, and lopsided Travelpro carry-on. Instead of replacing with the same or similar Travelpro plastic wheels, I of course went with the virtually indestructible (and much smoother rolling) in-line stake wheels from FA shop. Got white this time.

Just dropped these guys in - takes less than 3 minutes. No modifications as I did to the other one.

(Broken wheel on top)