We recommend osCommerce for businesses wanting to develop highly custom eCommerce sites.
In our experience, osCommerce has the lowest cost of ownership of any open source solution and therefore is cost-effective when it comes to offering a unique online eCommerce solution.
Although there are several WordPress eCommerce Plugins available, we recommend WooCommerce as solution for startups or small businesses that have a small product catalog where they have a story to tell before they sell.
Please note we’ve done Woo Sites with very large catalogs too!
We recommend Magento for multi-channel businesses operating within traditional eCommerce retail model requiring interfaces with major ERP systems.