Old fashion Oatmeal or shredded wheat and bran. ;)
Stopped by the store on the way home to grab some almond milk to make my workout shakes with (tastes better than making it with regular milk). I toured the cereal aisle, couldn't make up my mind which one I wanted, so I left without. Yes I'm a cerealholic! I was looking for some of the sugar free ones I saw online, but HEB didn't have any of them. I don't like any cereals with added fruit, nuts, sugar, frosting, etc. I like plain cereal. My currents in the rotation are Kellog's All-Bran flakes, and Post Shredded Wheat (plain). My choices were:

Cheerios (plain)
Grape Nuts flakes
Total (plain)

For any cereal fans here, which one would you choose and why?
Grainberry. 100% whole grain. I like the total grape nuts are dense.
If you wanted to kick up your health another notch you could stop eating this processed junk and eat only whole grains, things like brown rice, oats with dates, millet, etc. You're paying large corporations to process a whole grain they bought for pennies per pound. You'd almost be better off to eat the box than eat what's in it.
But there’s just something about opening the box, pouring it into a bowl, pouring the milk into the bowl, grabbing your spoon, and going to town!!

Cereal is fun!:D
Aquariuscsm, a question unrelated to this thread. I am curious about your avatar. Who is it and why did you choose it?
I also like breakfast cereals. But I'm a little more indulgent with cereals that have fruit and nuts. And I'll also go for the sugar coated stuff too.

But to your original question, of the three, my first choice is Grape Nut Flakes. I love the stuff. It just has more flavor than the normal grainy flake. In fact, I just picked up a box today. My second choice would be Cheerios, although I haven't eaten much in many years, I do like the grainy taste and texture. Total would be my last choice. I used to eat it quite a bit, forty years ago. But I got tired of it. Haven't had a bowl in decades.