I have used many shopping carts. Honestly Magento eats them all. Is unbelievable what this tool can do, is a beast of features and the best think about it is the huge module list available for it. Another important think about magento is its growth and expandability, that is really important for a shopping cart. I will never use a shopping cart that some random dudes developed on part time and gave it away as opensource, remember your customers will trust you for privacy and payment transactions. But on the bad site it will eat your server resources and might be really painful to setup/customize and use it. On the other hand if you need something minimal simple and yet powerful shopping cart i would suggest opencart. Is the fastest cart i ever use, with very clean code and ridicilusly easy setup and use.
There are many software available for shopping and cart and they all are really good, when we compare it with each other. 1. Zen cart, it is one of the famous software for shopping, 2. Zeuscart is also a great software and i love to use it. 3. 1shopping cart software's review is good.
There is lots of shopping cart available online and i think its totally depends on user experience one is good for one and same is not good for other.
I think that hosted online storefront is the best, muncom or ecrater. Recently i move my business to muncom, very fast and clean. free! regards!.
on hosted i would recommend shopify or volution for uk sites and bigcommerce or corecommerce for us sites.