I'd say the Optima definitely looks more sporty. Since it and the Sonata look very different from each other, it doesn't surprise me that some would have a decided preference for one over the other. I happen to like both quite well. The Optima unfortunately rubs one of my particular pet peeves: fake, tacky, cheesy, completely non-functional fender vents. They are not the only maker to add a serving of this particlar brand of fromage - and I don't like it no matter who does it. And the Cuisinart-style wheels on the top level SX don't do anything for me, either. But I like the greater range of colours offered versus the Sonata, and the availability of OEM HIDs aswell.
Jaeger