They are good infantry rifles - but not good dedicated gun fighting rifles IMHO. Trigger is on the heavy side. It is very well balanced. I have the tendency to wrap my fingers around the edge of the handgurad -ok for the full length, not so ok with the C-version. The ergonomics of the fire control is the same as the AR which I like. LOP is too long for me in close range shooting stance -unless I use the traditional rifle hold. It will be out of question completely if I wear "body bubble wrap".
The Mepro21 - I think people know what I think of it. THe owner complained about sucking in the exhaust from the ejection port. The rifle itself is pretty solid - for a plastic gun, it is much more confidence inspiring than FN2000 and G36 (which I had owned in the past) and less toy like than some of the late FN products.
I definitely will want to sling this at the mall , over an M16A2.