Luxoria - 2:25 am on Jan 25, 2013 (gmt 0)
I am using osCmax which is a loaded version of osCommerce. Basically, it comes with a few dozen preinstalled addons all of which have been tested for full workability. The developer team are active on the forums, make updates, and track down bugs. The software is free to use and is mostly compatible with 3rd party osCommerce addons.