We haven't had the opportunity to play yet but the MFM is a good possibility. We have met a few nice, solo males nearby that are open to "bi" as well as straight play.
I think there are a lot of reasons that MFM (or MMF

) are easier to get into. Here are some below
#1 There are so many solo males and their opportunities are often limited but their numbers really expand a couple's possible play dates.
#2 We have found that many we have talked to are more open minded or at least honest about it than the male half of a couple who may be curious but fears what his female partner will think of him.
#3 You have only one other person's schedule to deal with and solo males can often drop everything for a meeting.
#4 One less person to "click with" as opposed to two couples needing to get four people to hit it off.