The 12'x12' size is great.. Although just do make note to buy some bungee cords or something to tie down other than the stakes it comes with (those wont do much if you are in an open field with a little bit of wind picking up). I love how it came with a roller bag and there's a velcro pouch on the side of the bag to store the stakes.Just a note that it may or may not matter, but the Sierra II doesnt have their legs to be fully perpendicular to the ground (you would want to get the Pyramid or some other model instead). The Sierra's legs are angled when fully expanded, so just keep a thought if space or setup with straight-vertical legs are needed.