just went through the same senario recently. had been borrowing my brothers oztent cr1 for a while and found it a little small and the pole ripped through the fabric so was bit of a drama to set up then.
we ended up buying a wild country single pop up ensuite as it has 3 side poles you can insert to use as towel rails and poles for the roof to hang shower from etc, but found the side poles actually helped during windy times to keep its shape, otherwsie if just using as toilet you dont need to do anything other than peg out.