Never heard of SeedEdition, sorry. Chargify has a really flexible structure for configuring how you bill, with an api that lets you hook into it pretty easily.

Never heard of SeedEdition, sorry. Chargify has a really flexible structure for configuring how you bill, with an api that lets you hook into it pretty easily. The main drawback is, at least the last time I looked at them, the cost structure. It very quickly gets expensive, although depending on how much you charge, it might not be an issue. You can always roll that cost into your actual offering, as well