It depends on the product. In some products, there may be "network effects" where each user benefits by the number of other users in the system-- for example, i

It depends on the product. In some products, there may be "network effects" where each user benefits by the number of other users in the system-- for example, if Facebook were to adopt a Freemium model, the paying customers would benefit from having the free users in the system. This, of course, is not the case for most apps-- like Dropbox, in the example you chose. For Dropbox, the free customers have costs associated, but largely serve as a funnel. In other words, the costs of the free users are just considered part of the customer acquistion costs, the same as if they were Adwords costs with a given conversion rate. I don't think big numbers strike an emotional chord with VCs when it comes to financing rounds, if by "big numbers" you mean "big numbers of non-paying users", unless there are plans to improve the conversion rate on these prospects. If I were you I'd frame the question another way: given the product/app that you are planning, what advantages would a Freemium model offer over, say, a free limited-time trial of a paid-only product?