My wild guess is you get less accuracy with this “Deal” but you spray more so hit more. I have not yet read comments but that’s my guess .... No free lunch
No reason for accuracy to be affected. It’s the loading mechanism that’s different, not the chamber+round+barrel.
It’s not that it’s a free lunch, it’s that thanks to the 1986 MG ban, we haven’t had the market forces encouraging technological development. This and the FN P90 are the only real individual-sized MG innovations in the last 50 years.