I picked up a pctv HD mini stick 80E (USB2 digital ATSC/ClearQAM device) at Radioshack for about $32 (incl. tax)... was too cheap to resist.
It came with V5.4 of TVCenter - I installed it in Trial mode and it looked ok.
then on their website I saw there is a V6.4 which claims to require less resources (at cost of not being able to record direct to DVD or encode on the fly) and is hopefully more stable.

I installed that on a second PC in trial mode but found that the AC3 audio is disabled until you register/activate (I am still a bit confused about whether there is a charge to Activate it - I suspect not.). Also it looked like the EPG programming guide was not fully functional without activation. I don't suppose I will use the Distan facility to stream to a remote device.

Does anyone know how these two versions of TVCenter compare? Do I lose out in some way using the newer version? Am I better off using the Vista media center (I have Ultimate and Home Premium versions on two PCs)

Also the EULA seems to state that you can only install on one PC. Is that enforced through the activation key? In a family situation I would like to be able to switch the TV stick between PCs depending on convenience/need.

Any info welcomed!