Shopping cart decision

Hi there,

I am deciding to build my first ecommerce website. At present I am
looking towards Volusion (http://volusion.com),
MagentoCommerce
(http://magentocommerce.com)
and X-Cart (http://x-cart.com).

All of them have good and bad sides, but I am interesting at live
experience and level of sup****t.

As I have a little experience in this field and short on time for
personal detailed investigations. Any help will be appreciated.

Thanks in advance.