Just two points:
#1 - Of course, absolutely not man-portable. Not now, nor ever.
#2 - Its very same configuration makes it impossible to feed by modern systems. Do you see how does IT feeds? Five different ammunition columns. In which way are you fitting five AMMUNITION BELTS in it and making it work properly with ejection and all that stuff? All I have seen feeding by multiple ammo belts is a two-barrelled 20mm AA cannon made in South Africa, the two belts enter by the two sides and the spent cases and belt links are ejected downwards... and even then, the engineers had to work on it. A configuration featuring a third barrel (and of course a third belt) would already be impossible, how do you do it with FIVE barrels?
"It is criminal to teach a man not to defend himself, when he is the constant victim of brutal attacks. It is legal and lawful to own a shotgun or a rifle. We believe in obeying the law." -- Malcolm X
"We (atheists) act in good conscience because we believe in moral principles, not because we expect a reward in Heaven." -- Margherita Hack