To record two channels and watch a third under MCE you need three tuners. Whether they are on two cards of three shouldn't matter. So you could use a dual tuner and a single, or two dual tuners and have the capacity for 3 recordings and one live viewing.

I haven't seen any dual tuner DVB-S cards with CI slots though so that might mean you need three seperate cards if UPC Direct require subscription cards for their service.

Here in the UK, a lot of the satellite stations available are Free To Air, so I would be able to get away with two tuners without CAMs, and probably another one with a CAM to cope with encripted channels.

Are you going to be viewing HD content from these cards? If so you will need DVB-S2 cards. I haven't seen any dual tuner DVB-S2 cards anywhere. There is a reference chipset, but as far as I know there aren't any commercial implimentatioins at all. Which is a real shame. I'd love a couple of dual tuner PCI-e DVB-S2 cards for when I eventually get satellite installed