My biggest problem? I'm in need of a new body sooner rather than later. I don't know that I can wait for Canon to slowly come out with new tech. I've got a 5D Mark 3, and a 1DX (Mark 1). I've had my main board and my sensor replaced on the 5D3, and then recently had it modified by Spencer's. I've rented a 5DsR a couple of times and was pleased once I corrected technique issues, but I've been hoping/holding out for an updated version. I don't know that I'll be able to wait long enough and that bums me out. I wasn't impressed with the 5Dmk4 over my mk3 when I rented it, but I loved the huge leap in megapixels the 5DsR had over my 5D3. I wasn't seeing huge DR gains with what I shot on the 5Mk4 vs the 5DsR, so while it may be there, the type of shots I take don't necessarily show it.