HD receivers

[XXXL]

Looking to pick up a HD receiver but I'm a little worried about MPEG-4 support. The 2 I'm looking at are the SV8000 and VS9000. I've seen some specs for both showing MPEG-4 support but most specs only list MPEG-2.
Do either of these support MPEG-4? And if they don't will they be upgradeable? As I understand it, these are hardware based and will not be able to be upgraded. Just want to be sure before I drop $600 on one of these.
Thanks.

[Satbum]

I can tell first hand that the SV8000HD is a MPEG4 receiver and upgradable. I'm not sure about the VS9000 but I understand that is very similar in design.

[XXXL]

Thanks Satbum, that's all I needed to hear. I'm off to get an SV8000 tomorrow!!