Tempted to make use of the dish and cabling on the side of my house and plug in a HD Freesat box... But is it worth it?

I'd still keep my Freeview box and aerial, as the box is a PVR which is usefull, and the upstairs TV has freeview built in, but isn't HD...

Is it worth it for the HD stuff? Is there a lot on there? I know you can go to the site, but I wanted a real person, real experience views on it....