Help me out with the adv and disadv of each?

I believe that with a virgin HU card I can get it programmed and will be subject to whatever satellite providers do in the way of ECM

I also see that H cards seem to be very sought after, which I assume means that they are more stable. Can someone explain why? i.e. why should I spend more $$ on an H card rather than a HU card

Thanks

Ok we're goin to the newbie section...
You posted 1st in the dish newbie area...