I am looking at getting a new camera. I can't decide on the 6d or the 5dM3. I have the 40d with Sigma 10-20 F4-5.6 and the Sigma 50mm F2.8. I also have tamron 28-300. I have the Canon G15 for a everyday camera. I mainly shoot pictures not much video. I have three kids oldest is 10 and youngest is 4. They all play sports and I want something that will last. I do travel a lot and take pictures of landscape and architectural structures. I also am looking at getting the camera with the kit lens 24-105 and would like to get another lens either the 70-200mm f/2.8l IS II or the 100-400 f/4.5-5.6l IS. I thought about the 17-40 also but think my sigma 10-20 and the kit lens would be fine. I would like to keep the filter size the same at 77 so I can use all filers for all lenses.