Brilliant system!
I suppose you don't suffer from things like "building regulations", or "planning permission" in the North-east.
One question though:
It looks as ifyou are using standard "universal" LNBs on your 170cm prime focus dish.
This normally doesn't give very good performance, as the universal LNB only will see a small part of the reflector due to opening angle mismatch.
Now, I don't know the 170cm Megasat prime focus dish - it may be made to support universal LNBs.
Or did you just go with that dish because it was to hand? And the performance is good enough?