G1 not keeping focus
 

I've seen a lot of posts here concerning focus. Looking to see if anyone shares my experience. My G1 has focus drift akin to a back focus problem. If I zoom all the way in and focus, the image goes soft as I pull out to a wide shot. This occurs whether I shoot manually, use the instant focus assist or normal AF. I've spoken to Abel Cine Tech (where I purchased) and Canon tech support. They are going to replace the camera. Just wanted to put the word out and see if there are any shared experiences.