I set one of my shots as the background. It gives you window to crop the area you want as the bg. Its almost square because it pans left and right. Mine looks pretty good. I don't notice any blurriness. I can tell you that smooth gradients look like crap, though. I was hoping to show off some photos on the nice display, but anything with a real smooth gradient looks really bad.
I'm using this (square crop just left of center) currently, and it looks good.
This is an example of a photo that looks really bad. The model is fine, but the background is a splotchy mess of rings instead of a smooth gradient.