http://www.conversioncounts.com/blog/e-commerce/magento-ecommerce-seo-review/Magento Shopping cart has many features and a nice interface.  The down fall is  it is a hog. Do not try to run this on a shared server. 1and1.com shared hosting can hardly run it. The other this  moving the site restoring a back up is vary difficult. I have not had any luck doing upgrades the sites end up crashing.  When I first used it  I liked it  now with the upgrades the  memory and process hog  I am being forced to switch. 

If you have deadicated server  the go for it.

PD