[D.L.M.]

If your gonna bet then you can bet half the pot, chances are the this flop didnt hit anyone. If they dont fold to cbets often then you know what to do.
The thing is that if you bet you can get mp1 to fold a few more hands than he would HU since he has to worry about mp2. So since mp1 is more likely to fold and mp2 has a shittier hand since he only came along after mp1 then id say you can bet alot of the time here.