There is no such thing as a "hero weapon" guys, i know that is what TWI told us that the MKb and AVT would be when they where first announced, and most of the forum community seems to have clung to the belief that this would indeed be the case ever since, even going as far as assuming that other rare unlockables, like the Nagant silencer and MP-40/II would also be hero-only.
But it's not true, it either never was, or plans changed, because there are no hero-only weapons in HoS, and this was revealed ages ago in the Bash-cast hosted at TWI's offices, and further cemented durring the Prague-event and ever since.
People have just refused to belive it, and kept clinging to the idea that it would be hero only, because that's the only way it could make sense to them.
But it's time to face the facts guys, and from what we know, the only limitations on rare weapons and attachments is that "you have to unlock it first". But once unlocked, that's it, you not only have unlimited access to it, but you are forced to use it, because TWI feels that "it woulden't make sense for a soldier to choose a lesser gun if he has access to a better one, so you will just use the better one".
So yes, it will only be a matter of time before all thouse MP-40's you see on the servers, will turn into MP-40/II's, and we could all have silencers for our Nagant revolvers, and even the MKb and AVT will allways be in play because it belongs to the "Elite" rifleman, not the hero like people assumed.