Premium Membership Site With a Store, How To Merge Login Info

I am planning a site that has member’s only premium content area, but also has a store that sells products to members and non-members alike. Are there any complimentary membership and e-commerce plugins that can share login information. I would prefer members to not have a separate login for the store.

I’ve played around with S2Member and am leaning toward it, but am open to any combination that would work best. Some e-commerce plugins, like woocommerce, have login or member features, but the primary purpose of the site is the membership area, and I need a more robust feature set than the ones included with shopping plugins.