The thing that most missionaries do nowadays, and something that I did toward the end of my mission when it was available, is carry a couple of the blue BofMs as well as the newer blue Bibles that don't have the references at the end and these are used for street contacting and tracting while using the larger personal set for studying and teaching set appointments.
Personally I preferred my quad as a missionary because I found it easier to handle, but to each his or her own. Seeing as you've already decided on the separate books that a moot point anyway.
For missionary scriptures I would definitely go with the standard size edition, and in my experience the real leather, while a bit more expensive, hold up a little better after hours of study.