Yeah, remember that if you're using it right, that particular VTOL is going to be out of range of every single other unit on the map when it takes the self-inflicted damage, and probably out of range by double digit hexes, even, including LRMs and ER PPCs. That goes a long way toward mitigating the flaws.
a mission-kill is still a mission-kill, it means that through no action of the enemy, you're down a unit, and it's a guarantee that eventually, it WILL happen. Even in BMR days, a 'mech with locked up legs from MASC failure could still turret for a while before being taken completely down, but a VTOL isn't a 'mech, once it's mission-killed, it's out of the picture as a useable asset, with the destroyed rear armor, it's not even particularly useful in a spotting role, esp. if the opposition brought their OWN choppers...stunned crew just don't fly evasive very well.
for that matter, they don't spot worth a damn either.
It's got the Yellowjacket problem, but applied to a different set of circumstances. That problem being, "It looks great on paper-if you ignore the fatal flaws."
Put it another way: would YOU climb into an aircraft with a 1 in 36 chance of exploding
randomly as part of the normal function of its systems? would you carry a rifle that, without you doing anything wrong, as in, no operator error or enemy action involved, that explodes randomly for some reason the engineers can't quite figure out yet?
On a properly designed, ground-bound unit, this isn't a major problem, but the variant we're discussing (in this tangent) is NOT a ground-bound unit, with separate turret, that can still be used to bunker if the gun breaches for no apparent reason.