I used to customize online stores built with LaGarde StoreFront 6.0 but eventually every shipping and payment processor API it used changed and then it no longer supported current SSL protocols. That is a perfect example of how the Internet is always evoving and breaking prior technology.
My new E-Commerce solution is the UberCart module for Drupal. I have extensive experience with UberCart because we use it at work to sell tickets. I have also created a fully functional online store to sell my old technology books at Williamsport Web Developer Books. I'm not really trying to run an online book store. This web site is primarily to demonstrate my E-Commerce solution. I have customized the web design of a standard Drupal site and created a custom content type for books as a product. You can actually buy one of my old technology books from that site. However, the site is not secured with SSL because I don't want to pay for a SSL certificate on a demo site. I also plan to experiment with search engine optimization with the www.wwdbooks.com site to see if SEO can be used to sell products which are hard to get rid of.