It really depends on what you mean by infinity wall - if you are talking about just the transition at floor level having a fixed curve, then fine, but add an overhead background roller system as well. If a full cove, then see bellow
Been using a large cove (full width, with curved transitions at floor/ceiling/right hand corner) for the last 6 weeks or so and a few thoughts are:
-Very nice, but a bit of a one trick pony, unless you have very good lighting - easy to get everything white, but more problematical if you want other effects or colour changes.
-Needs an overhead track system (if full width) for lighting behind subject.
-PITA to keep clean, but that is based on the one Im using which sees lots of traffic.
-if you only have one 'shooting wall' it's a waste of space IMO.
-if you only have a cove and nothing else it will stifle creativity.
As for building one, full cove (floor to ceiling & edges) the transition in the corners is the only problematical areas as far as I can see. For just an infinity wall seems simple enough (floor & ceiling transitions only).
So, if I had several (largish) shooting areas, Id have one, if I didnt, I probably wouldnt bother or if I did, Id still have to find some way of adding a background paper system to go over it as well.
Paul