I have used Interspire shopping cart for few of my ecommerce websites and the product is really amazing. The only thing that hurts is it is quite expensive.
I really like the templates and within few customization you are ready to go live with your website.
To use Interspire shopping cart, one doesnt need to be a programmer and with basic html skills you can easily setup the website.
You can add videos,images in your product description. You can shopy by brand, shop by price as well as define discount rules easily for each product.
You can also set product discounts on user groups.
I will recommend using Interspire shopping cart if cost is not a constraint.