The Freesat receivers are plug'n' play once a working dish has been installed.
FTA receivers like the one in B&Q will require initial tuning and periodically after that too as transponders and channels change.
For a cost point of view the b&q system is better, I have seen the dish and it should be OK.
If you just want to watch TV, and not interested in learning any satellite stuff, want a reasonable epg, then thw Freesat system is best, but it will cost you more.