What is the best shop plugin to use?

I am trying to get a simple shop working. I have some knowledge of css and minimal PHP. I have tried wp-ecommerce, which seems to work, but won’t allow me to use Google checkout for some reason. I have done some research and it seems many people have issue getting it to work smoothly. I like the google checkout option as well as Pay-pal. Is there any other easy way to integrate credit card payments?

The site I am trying to get a shop working on is http://www.baconwizard.co.uk At the moment I have wp-ecommerce running with Paypal, but I think I would like to try another plugin, which one should I use?

Rob