I have an x10 which I use alongside my slr system. Most of my pictures are of people in informal situations sometimes in low light. I really enjoy the camera and it is well suited to photographing people. Here is my dilemma. Focusing can be a problem. I use the ovf almost all of the time and find focusing is not always reliable. Probably losing 25% of shots due to focus past the person or hunted in low light. I find the image quality great. Is it worth upgrading for the improved focusing and the focus readout in the ovf of the x20?