It would be surprising if, for data with a consistent, predictable structure, MongoDB had the best, most consistent, and most predictable performance. MongoDB's

It would be surprising if, for data with a consistent, predictable structure, MongoDB had the best, most consistent, and most predictable performance. MongoDB's raison d'etre is that data doesn't always have consistent, predictable structures. That said, there's cool stuff out there in the Mongo ecosystem. E.g., TokuMX is a whole new Mongo storage engine.