It really depends on what you want to do with the player. If you're not going to use the analog outs (i.e. digital outputs only), the 105 is extreme overkill; the 103 will do everything the 105 does for less than half the price. There's nothing wrong with the 83 and 93 (I had a 80!) but there may be some features of the 103 you'd miss. Certainly the players got better over time. Any would be compatible with Blu-ray video and audio formats with just about any HDMI receiver less than 10 years old.