Seriously, you're gonna continue even after being warned, purvue?
There was no frickin' attack. csbrademeyer
essentially admitted to trying to break the game. Everyone
else here agrees that the only one attacking
anyone here is
you. Lay off it, already.
A lot of what is in the game that appears to be conflicting - gas-vent and sound suppressor / silencer combinations, that sort of thing - are pieces of legacy gear. DeathStrobe, BetaCAV, understand that 4e (and thus 5e) rolled back the crunch on gear design, and because of that a lot of the picky options are flat-out
gone. Even then, though, getting a system that combined gas-vent with sound suppression required building the weapon from the ground up, essentially designing it that way. In SR5 terms, however, you can explain such 'you can't do that by the modification rules' items as being a matter of proprietary technology that little nanobots chew apart if you try to probe them, that sort of thing. "When we try to open it, or even x-ray it, it stops working and turns into goo."
SR4 and SR5 require a much more casual attitude towards 'how things work'; handwavium is in much greater supply, in order to increase the level of 'get on with the game already'. As a consequence, you wind up running into confusion of what works with what, doesn't work with what, and why the Ingram-Z has a Wotcher and a Whosit when it's obvious you can't actually
have a Wotcher and a Whosit on the same weapon according to the rules.
"Because it does; let's move on." That winds up being the reason given, and appears to be the intention. I don't say it's bad; I prefer more crunchiness, because I
like having a slimline MAD-invisible combat-reinforced pistol with smartlink, improved rangefinder, kickass damage, and yadda yadda that uses ammo that costs three times as much as 'normal invisible-to-MAD' ammo does, which weapon costs ten times as much as any other pistol in the game, is thirty times as difficult to get your hands on in-game, but which to me is worth a
hundred times as much, both in story and in personal satisfaction, because it's My Unique Kick-Ass Gun, Fear It In My Hands, Ye Mighty, And Despair.
If you want the crunchy, my advice is still - and will pretty much always be - to go back to the 3E Cannon Companion, look at how weapons are built or modified, and figure out what works and how much it's going to cost. Because it
will cost a boatload. You'll fork over for an SMG what you could use to buy an entire reconfigurable weapon system - pretty much just so you can say, "Yeah, I got this sweet supercalifragilisticexpialidocious-special gun. Ain't it cool to be me?"
And that is part of
my rule of cool.