Following my previous question, I'm now evaluating the possibility of using a hosted platform for the ecommerce project I have to implement. Before I start "playing" with each one of them, I'd like ask if anybody knows which ones allow a good degree of customization.

At the moment I'm looking at BigCommerce, but it seems that customization is limited to templates, while I need additional features which require PHP Coding. Also, I'd need to be able to import additional product data into the system, and I'd need to do this via code; I had a look at some integrations, but they gave me the impression that they all run on the rendered page via JavaScript. For example, if I want to show Facebook Reviews on a product, I'll have to add some JS that will fetch it and show it on the page. This is not optimal, as I must cater for people with JS disabled, therefore I'd need to run my own PHP code.

Thanks again for all the opinions.