The Comparison between Magento eCommerce and X- Cart can be made by studying their respective advantages & Disadvantages.
Magento is one of the newer shopping carts on the block but has already attracted a large following. The coding is based on the latest PHP 5 object oriented coding standards and the Zend framework.
+ Varian the company who backs the cart is very active in updating the code and fixing bugs
+ Multi-Store Capable
+ Nice default template
– Heavily layered and overly complicated coding style and thousands of files requires a lot of time to learn and do customizations. Estimate about 2 – 5 x more for your budget for customizing it vs. other carts
– Right now the technical documentation is very limited, making it difficult to customize and modify the programming of Magento beyond doing graphical changes.
– Runs fairly slow. Plan on spending at least $25/month for a 1000 product store, or $50 – $100 month for stores with over that.
X-Cart is a commercial package, but one of the most competitively priced and easy to modify.
+ Commercially supported and has very few if any bugs
+ Uses Smarty Templates system which many programmers like to work with for laying out the web site
– Licensing fees for system