I think, the freemium model works best, when the resources needed for one additional customer (including computing-power, storage and support) are relatively ne

I think, the freemium model works best, when the resources needed for one additional customer (including computing-power, storage and support) are relatively negligible. Many companies operate the freemium model with much less than 11% conversion rate -- but the additional customers they have to carry with the others are not so a heavy burden. The advantage of the freemium model is faster scaling and adoption of the service -- but with the cost of an additional burden ... and you have to know, if your business can carry the weight or has to do differently.