Sunfire Question

[4Hawks]

I'm fairly new to the home theater game, so bear with me as far as my knowledge base (especially connections).

I'm planning on upgrading my equipment to take advantage of HDMI and currently own a Sunfire Ultimate Receiver and Arcam DV-139 player. I would like to stick with Sunfire since I have been very happy with the overall performance and have always been a Carver fan.

My question relates to the TGP-5 and the newer TGP-401 (I looked into trading up to the TGR-401 but have been unable to find an amenable dealer, so I'm planning on using the older receiver as an amp and purchasing a newer processor).

I heard that there is some kind of incapatibility issue with 1080p processing with both units, so I did some research and, from what I can discern, it appears to be with Blue Ray audio signals only(?). The Arcam upscales to 1080p via HDMI. Would this be a significant compatibility problem or not? I would appreciate any advice, but keep in mind I'm not familiar with most of the techno jargon. Thanks.