I have used both, but lean towards Seafoam more often. I seafoam every used car I get my hands on...the stuff works.
Seafoam is a great carbon deposit remover....suck 4-6 oz. into the intake via a vacuum hose, shut the car off.....restart it 15-20 minutes later and let the carbon smoke burn off in the exhaust....put some in the oil, put some in the fuel tank.....enjoy a smoother, more powerful engine for about $6 a can.
Good Stuff!