There's a difference between a challenge and going that far. A challenge is fine, but going that far is not.
How? Give some support to your claims.
No, there is not a "big difference" between those two types, there is a very fine line that is exceptionally easy to accidentally cross.
Hmm...well can't be a killer GM if you don't, you know, kill lots of PCs. If your players keep coming back for game after game to the point that you never get to play because you're always running, probably not a Giant Flaming Asshole GM, because players run like the dickens from those. Again, you could actually support the claim instead of just using it as a point with nothing to back it up. How are they very close? Why's the line accidentally easy cross?
As to the mention of the cyberarm, well, you should think twice there as well.
Why? The PCs are Shadowrunners. They go on cover ops missions against corporations with vast resources, illegally. Unless they're stealing puppies and kittens from the local pound, the target corp is probably able to pull out enough stops to seriously frag up a character if he messes up. The character is better off damaged than dead. End of story. Why should I think twice? Again, support.
The last part, yes it is metagaming, since--as stated--it is highly unlikely that without a serious fubar on the part of the player that any opponent would ever be able to learn about said flaws without delving into GM metagaming, and if the GM metagames, he has lost all rights to punish the players for doing so.
So the NPC needs to know that the character has sensitive system to implant him with Moleware
TM? That rescue ship of foreign smugglers has to know about the random person on the island's allergy to be offering them a cup of warm soup and a mug of pick me up goodness? Johnson's have to know the biometrics of every character when offering access to what they have on hand as a bonus for a job well done?
That's just absurd. The NPCs don't know. They are not metagaming at all. The
GM is bringing the flaw that the character took into the game in each circumstance. If that is Metagaming, well hell we might as well yank out all contacts, guns, response plans, and every offer bit of the game that can be used against the player. After all, running an adventure is metagaming. The GM knows what is going to happen before hand.
Sensitive system does not need to mean that cyber needs to be forced on the character.
I never said it does
need that. I said it's one valid option of bringing it up in play, making it part of the characters story.
you had an example like it, but the example relied on a stupid Johnsen
So giving the runners a bonus from what he has access to is stupid? I fail to comprehend that.
Or you are saying "my character's system is sensitive to cyberware", also, why is that the way to explore what being sensitive to chrome is like? And what is so wrong with a little munchkining?
A.) You don't have to have Sensitive System to be sensitive to chrome. You can simply decide your character is sensitive to chrome and have a nice day. Just like you don't have to take Poor Self Control to play a character that is a thrill seeker, but if you do take it, the GM should bring it up whenever the situation crops up.
B.) I believe Munchkining in this sense is the "I want the points but not the drawbacks, whaaaaaaa," attitude. There is nothing wrong with building a solid character. There is something wrong with exploiting rules, or taking things you don't want for you character just for the points and bitching later when it crops up during play.
C.) I've offered several ways to bring up sensitive system, none of them were ever stated to be mandatory, only fair. Taking Sensitive System and ignoring it isn't saying "I'm a little sensitive to ware", it's saying " ". That's right, it's saying nothing. At the very least, the character should occasionally be facing some hard choices based on the flaw he's taken.