I don't think there are any. In what way was Ogone a serious hassle? Was it difficult to get to the point where you could accept payments? Payments that didn't get processed correctly? Downtime?
Ogone works when you get over the draconic configuration and contact setup with banking instances. From a technical point it works good but please don't get me started on the user experience, that's just one big fail from start to end.
