I used to have a 2 man bivvy, it went on every night /24 hr session... Honestly it was Maooosive, me n my lad could have a bed each in and still room for another...
Now I'm on the Sonik AXS Brolly and Wrap, up and standing in about 10seconds (Honestly)... For the price of Brolly and Wrap you could go straight for the Sonik AXS Bivvy, but as a brolly, it caters for days and nights, if it gets abit chilly throw wrap on, it's also Pitch black with it on...
There are different AXS versions.