I've had DirecTV for a bit over a year now, because my landlord and I split the bill. I can't say I'm convinced about the picture quality, but it's the only service I've had with my Aquos.
My 360 looks great on my set, DVD's seem ok but I can only view them at 480p.
But the HD stations look like they have a lot of artifacts and noise compared to what I see on other people's sets, and non-HD channels look undersaturated and look really compressed. Is it my TV, or does Direct's broadcast quality just suck?
