Hi Gordon,
Is there a reason why you would want to buy one of those. It looks a very expensive piece of kit and easily removed if you have not got your eye on it. It states you still need 50ft of cable to get a signal if you are in a wooded area, thats provided you have a clear view towards the satilite.
I use an old sky dish the type used on houses (cost nothing) my sky hd digi box from the house (only cost, my subscription to sky) a tripod to enable me to move the dish around for signal (cost £15 from ebay) Total cost £15 and I get sky every time.
To be honest I have had a look at the video ad for it and I just think it is going to be very expensive for something that is not needed. In my opinion save your money.
http://www.youtube.com/watch?v=lX7D_E-zgww
HTH
Graham