This test wasn't nearly so blind as many of my others have been. My apologies if your sense of scientific adventure is spoiled.
Here's the back story. My wife refuses to eat anything but Cheerios, but based on $$$ I bought a box of Walmart's off-brand toasted oats for the baby's snacks at church. Since we had them both, I ate a bowl of each.
The Cheerios were nice and cruchy. They have a balanced oat flavor with a nice after-taste. I prefer unsweetened cereals and these fit the bill nicely. They have good taste without being sweet.
The Walmart brand didn't have the same crunch. It's hard to describe, but even out of the box they just weren't as crisp to the tooth. Maybe a little stale tasting, but that's not quite the right description. The taste was pretty similar but wasn't as pleasing.
From then on we've been a Cheerios household. The baby even enjoys them more. Who'd have thought he had such discerning tastes?