You need to decide which platform you wish to record from, DTT, Dsat, SKY, cable or all of them.
With the exception of TIVO all the current and upcoming HD based recorders with digital tuners will be tied to a particular platform.
At this time the PACE Twin has two digital tuners and the upcoming Humax 9000T, Fusion FVRT100 and Thomson DHD4000 will have two tuners.
You do know that the SKY+ sub is waived if you have a suitable channel package, great if you already subscribe to movies or sports but no help if you don't
If there is a film on both BBC1 and Channel 4 starting at the same time i would like to be able to record both. Currently i have neither a digital receiver or SKY. I do not intend to go for the SKY option as the FTV channel are perfectly adequate for my needs.
I know the Pace device has two tuners and i have even downloaded its manual to see if it has dual record, and it does not appear to. It can record one channel and watch another, record and playback an old recording at the same time but no mention of being able to record two channels at the same time.