I once read an account from a Russian military police captain who was visiting the LAPD as a guest. After watching a house-clearing live fire training exercise by SWAT entry guys armed with MP5s and non-lethal 'flash-bang' grenades (done perfectly because they'd trained the same scenario hundreds of times before, of course) the Russian captain was asked 'How do the Russians handle the same scenario?'.
He said that instead of rushing into the room in a single file, throwing flash bangs, and engaging individual targets in short 9mm bursts like LAPD SWAT did, his men just stand in the corridor outside with their AKs and fire into the room through the walls in 'Mad Minute' style emptying three mags full, and THEN they toss general-issue frag grenades inside.
I know you didn't ask me, Travis, but I don't see any downside to bullpups at all.