Well you know, I like Empress Miniatures, I like USMC...
Back in time I ended up backing the USMC-PLA kickstarter... the figures arrived last january and I did the first USMC fire team quite recently.
For now just look at the really nice figures. They have opted to do the fire teams basic pack with the M27 instead of the M249. Well at the moment the USMC seems quite happy with it but I think you are just removing suppressive fire capability from the team (oh look the 3 teams concept was created for suppressive fire. Well it is the USMC anyway usually they end up messing with equipment quite often...).
Anyway enjoy the four guys!