Weapon, Chorister Series, not allowed for SFS play?

[camberme]

The subject kinda says it all
The weapon https://aonsrd.com/WeaponDisplay.aspx?ItemName=Warbler&Family=Chorister
Doesn't seem to be marked as legal for SFS play.
The scenario it is in... is Legal for SFS play.

I wonder why though the weapon isn't?
Operatives have "their weapons"
Solarians have theirs,
Vanguards get their shields
Bioengineer's get their computers

Why don't Envoy singer's get something?

[Xenocrat]

It's too strong relative to the other boost pistols (Forked Pistol, X-notch) in Armory. Compare the level 2/6 options that directly match up to the Choristers at the same levels. Those are plasma E/F, which is generally worse than Sonic, they have shorter range, and they have lower boost damage values.

[BigNorseWolf]

EAC weapons (especially sonic ones) are supposed to do less damage than their KAC counterparts. This one seems to do as much damage as KAC weapons of the same level.

[Claxon]

Yeah, whoever wrote that kind screwed up on the balance.