Thanks for your interest in the Simple Affiliate Shop.
The plugin would be great for showcasing individual CFD providers and letting you either show them as a 'product' in a store or to manage banner adds in your sidebars via the standard text widget and the short code for banners.
It does not currently have a comparison engine as the idea is to keep this simple for a start and make it easy for people to get going in the world of affiliate marketing.
I'd suggest you download it and have a play with the options it has. You might find that the categories would allow you to do some simple comparison by offering pages the filter out CDF providers by feature. I'm not an expert on CDF's but you might separate the out by those offering different currencies, types of CFD offered etc.
Good luck with your website and if you have any suggestions for the Simple Affiliate Shop plugin then I'm always open to hearing them - the best way to do this is via the website contact page http://www.PeoplesGeek.com/contact/
Brian (People's Geek)