This is a very narrow outlook. Some people's ears stick out more than others and are more prone to getting rubbed on or bumped. Your experience is one end of the spectrum. I, on the other hand, started getting cauliflower after a couple months of training - from the pressure of my opponents controlling my head from side mount, back mount, or reaching through when I was turtled. "Don't let those things happen to you" isn't an option for a comparative novice rolling with upper belts.
I have used a Cliff Keen F5. It was ok, though I always had trouble with the forehead strap dropping down near my eyebrows no matter what adjustments I made elsewhere.