Important question. We were using the Leads module but due to it's bad design (only having one person & company per lead and how it is a different structure than Account/Contact) we are considering abandoning using Leads in favor of using Accounts for all companies with a field that categorizes the Account as Prospect or Customer.
This solves a lot of usability challenges but to use Lead Scoring in the Marketing module a Lead is required. Overall this is a problematic and very complicated design how Microsoft treats Leads differently in Marketing than in Sales.
We created a plug-in that will automatically create a Lead for every existing open contact and will then automatically create a lead (connected to the Contact) for every new contact that is created. This should give us all the necessary records to allow us to use only Accounts/COntacts in sales but also leverage the Marketing features (lead scoring).
Can anyone think of anything we may be missing in this plan? Appreciate any input.