I agree with you. I can give some reasons more. Here are some advantages of Magento:
Open Source
Magento is free for download in the Internet, except Enterprise version. It includes most of the necessary features to have your store up and run it.
Feature-rich
Magento’s admin area is second to none. It allows users to be enabled full features by the click of a button. It is easy to look at your website performance and real time information. Magento allows third party integrations to import products from spreadsheets, manage newsletter system, start-to-finish manage an order of a customer.
Flexible CMS
It supports you manage multiple websites, integrate Google website optimizer and over 50 payment gateways. WYSIWYG editor is friendly to help non-tech individual refresh website easily. Magento is perfect choice for product editing and capable of handling large database smartly.
Strong Community
Magento is owned by eBay. Magento users receive an abundance of helps and advices from eBay advocates to manage effectively. There are over 800.000 developers worldwide with Magento experience.
Extensions
There are about 15.000 Magento plugins and extensions.