The bleeding edge for pixel-pushing displays has shifted, and 4K, aka Ultra HD, is the one to watch. Though the once-great 1080p HD specification has now become commonplace, seven years ago, it was an altogether different story. Pioneer, one of the leading manufacturers of plasma televisions at the time, chose to buck the popular trend toward pricey full HD sets, and instead focus on more affordably priced sets under 60 inches.