If we are using a normal dual pole lnb and if we are connecting this to 2-receivers, if one of them watching H type channels, then the second also can watch H type channels.
But if we are using a "Single solution lnb" both can watch programmes independantly. Means one can watch H channels and other can watch V channels as per their convenience.
This is the major difference. This type of lnbs marketted by Eurostar initially.