E-commerce

Hi all, I'm wondering what experiences people have had with e-commerce/shop building software. I've looked at oscommerce and I must say it's very impressive. the only thing against it for me is that all shops using it are forced into the same boxes left and right style layout. As complaints go this is not a major one, but I am looking to move my existing shop from Erol and wouldn't want to make such a massive change in the look and feel. So to the questions. Have you used other e-commerce/store building software? What were your experiences and what would you recommend? Regards, Dave.