In reply to Mick Bradshaw:
I can thoroughly recommend the Alpkit Axiom, spent 2 weeks in Scotland in April, withstood the wind and rain, (though has to be pitched facing downwind) and can get hot when it’s hot. Sleeps 4, albeit with a curtain separating the inner into 2 areas.
However, it has a very roomy vestibule, room for a table and two chairs, and the clincher for me was that it packs up ridiculously small and light, about the size of a carry-on. And I can just stand up in the outer at 6 foot. Might be a bit crowded for 4 adults though.
Seems Alpkit are now doing even bigger stuff, maybe worth taking a look, but the strong point for me was the packed size.