I'm not familiar with any of these cameras but they all seem to be of the point and shoot variety. If that is the case, and if you can deal with the shutter lag, I'm sure any of the three will give you great snap shots.

I have been using the Tamron 18-270mm on my Nikon D60 for 4 years with excellent results as a walk around lens. When I went to the Nikon D600 I tested both the Nikon and the Tamron 28-300mm lens. I choose the Tamron for several reasons. I saw no difference in sharpness and picture quality. The Tamron was noticibly lighter, important if you are carrying it all day long, and it was a lot cheaper. If you have a DX sensor I would choose the 18-270mm, if you have a FX sensor go with the 28-300mm.