Never heard of Hankook? You must not buy that many tires.
They're a fairly common ful line tire manufacturer, like a Bridgestone or a Goodyear - they make tires to fit all kinds of applications. The Optimo 725s are a mediocre, budget-minded, middle of the road all season tire. It won't grip like an R-compound, it won't go through 8" deep snow like a studded Blizzak. It won't have ultra low rolling resistance, high carrying capacity, and it won't be astonishingly quiet or anything like that.
Why? Because those are things that you buy specialized tires for. Those are things you pay more money for.
Reading through the reviews, people seemed to be disappointed that these tires won't do things that tires at double the price will do. Go figure.
What they will do is give you an acceptable tread life, acceptable grip, and acceptable comfort and noise without costing a fortune.
So it depends what you're looking for. Would I go out to buy those tires specificaly? No. Would I buy them over some other brand if the price is right? You betcha. Would I replace them for the sake of replacing them on a Malibu? Hell no.