As a marketing representative for Answerbase.com, I would recommend selecting an e-commerce provider that allows for product discussion and feedback. This can greatly increase the customer's satisfaction by helping them avoid items and products that are not exactly what they are looking for. If the provider you have selected does not offer this feature, Answerbase can easily be integrated into you existing site as easily as adding a widget directly on the product page. I would recommend checking out the other benefits of Answerbase such as increased site traffic due to search engine optimization to see if this might be something that will integrate well with you existing site.
http://answerbase.com/social-e-commerce-Q-A-platform.aspx?lp=0&ABVersion=B
Regards, Josh