Humax hardware seems to be getting a good write-up. It's no guarantee but I've installed a Humax Freeview box for someone and it's good quality rx, easy to use and well-built.
Do the prices for Freesat boxes vary greatly? Whether you want SD, HD or PVR, the prices for camparable facilities seem to be about the same at the moment. Installation will vary depending on where you want the dish. It might be worth getting a price for installation from a local aerial man and buying the hardware. It's not difficult to put up the dish yourself - plenty of help on the ASTRA website along with (last time I set up a dish) a little application to show exactly how to align it.