We recently faced this same issue. I did a lot of research and found far more opinion than fact. It was very frustrating.
I considered Joomla and VirtueMart, but bypassed it due to worries about unnecessary complexity and poor performance.
I settled on oSCMax, a fork of osCommerce. ZenCart, another osCommerce fork, was a close second.
We also looked at Magento, but passed over it because of concerns regarding performance and maturity.
Then, almost unintentionally, we bought an eCommerce site built using PrestaShop. Our goal was to standardize on one platform and now we have two.