i just got my panasonic 50in plasma. the native reolution is 1366 x 768. which resolution should i set it with 720p or 1080i? i'm using to watch hdtv, blu-ray dvds, and playing ps3 games. some articles say 720p is better and some say 1080i is. also is there a big noticeable difference between 1080i and 1080p on a 50in plasma?