I think the D610 would be perfect for weddings but yes you need to get some good FX glass to go with it. The D800 can be used for weddings but the workflow with the huge files is a whole 'nother ball game. The D610 files would be much more manageable. The D800 is almost too much camera for weddings because of the sheer amount of images taken on a given day. For one wedding afternoon I had over 60 GB of images from my D800 so it isn't trivial in terms of file management. Just converting them from NEF takes quite a while even with a fast computer. So if you get a D800 plan for $80 per 32 GB 1000x card, faster computer, lots of external multi-terabyte storage, etc. on top of the cost of the camera itself and pro glass.