I have been using round section handlebars for years. I swapped out my old bars for these primarily for the flattened tops. Installing them myself pretty easy. The groove for the cable-casing was tucked nicely away. The shallower drop and shorter reach was an added bonus: the cockpit now feels like it fits me just so -- and no more sore hands.
I preferred aluminum over carbon, obviously for price, but these are just a few grams heavier than carbon, and even though it might be a superstition on my part, having had a friend break carbon bars, I feel more secure with metal for this part.