How well does Windows 7 MCE support Clear QAM?

I use a Hauppauge 950Q and it does ClearQAM fine - in fact Win7 downloads correct driver for it. I have had issues with MCE not showing items in the guide for ClearQAM channels. One thing to consider is the type of card - the 950Q is USB and offloads the compression work to the host machine. Generally it does fine on a fast machine but activities on the host (like a windows update download) can cause stutters. A card that does compression on board would be better. HDTV, recorded or Live looks really good on MCE.