Well, if the Xbow doesn't get a reload speed bonus (even though the perk description says so), why would the M99 get it? If TWI fixes the Xbow (i mean, make it slower to reload offperked, but make it benefit from the Sharpie reload bonus to make it as fast as it is now (equal to the bugged speed*)), then yes, the M99 can get it too. But right now, the base of the game is so inconsistant with its descriptions anyway so the M99 honestly doesn't need much tampering. Only thing it needs done is the damage numbers i proposed to Ivan or Jack Carver and that's it.
* By bugged speed, i mean the actual fastest time you can shoot currently, which is really ugly animation-wise, because you can shoot a new bolt before the reload animation is done. The animation is perhaps 1.9 sec long, but the actual reload speed is only about 1.6 sec long. And yes, this is both perked and unperked.
Here is more in detail to explain what i mean: