Integration with Magento (or other ecommerce app)

Hi,

I am looking at integrating an EPiServer 5 install with Magento, but I think this is probably relevant whatever the platform.

I want to create a link between an EPi User and a Magento Customer. My initial thoughts are to store the newly created Magento CustomerID as an additional property in the EpiServer Profile but I wondered whether anyone had any other thoughts/alternative approaches?

Furthermore, to integrate these 2 I need to create single sign on. So far I have taken the rather rudimentary approach of adding code to the login control, would it be more sensible to extend or create a new membership provider?

Any advice/thoughts welcomed