we only had one and would put the second baby down on a regular blanket with toys, but then we realized that both of them preferred the regular blanket with toys anyway and stopped using the activity gym altogether.
We have been fine with 1. They always liked being on it together anyway...now they are gettinga little big and Emma rolls around and gets irritated by getting stuck on the bars, so we will probably be retiring it soon!
Re: 1 activity gym..or 2?