HALP! We currently use the out of the box connection to SFDC and using contact roles I'm able to get a full circle view of my leads -> customer lifecycle and an OK attribution model.
SFDC Opportunities present some challenges to the company in general because of the way we sell and how we want to use the Product object in SFDC. They are talking about having someone to build us a custom object to use instead of Opportunities. I told the team that Marketo only connects to a few standard objects (like Leads, Opportunities) and that we need that full circle connection via Contact Roles to get us attribution so if they want to build a new interface to sit on top of Opportunities but it makes changes to the actual Opportunity object, it might work, but if they build a separate object that does *not* update Opportunities, Marketo can't see it.
Their answer is "Marketo has an API that we can write code for and grab/push data as needed". Is anyone else doing this that has SFDC but has given up on Opportunities and manages to make it work in a good way?