I'm trying to figure out the exact ramifications for STL on the Raven RVN-4L as it involves "being affected by a hostile ECM" and the two abilities PRB and SNARC (or indeed any other abilities on the unit with STL, that is what are the actual drawbacks?)
PRB ACTIVE PROBE pg 82
Hostile ECM systems, including Angel ECM (AECM) and standard ECM (ECM) will overwhelm the active probe’s abilities.
STL STEALTH pg 79
Any non-infantry Stealth unit is affected as if in an enemy ECM field (see ECM, p. 77)
ECM ELECTRONIC COUNTERMEASURES pg 77
ECM vs. Active Probes, Drones, Narc, and iNarc Systems:
Active probes, drones, and the Narc/iNarc systems are all covered in the Optional Rules chapter (see p. 136), and will detail the effects of ECM against those systems.
(not super helpful)
SNARC NARC MISSILE BEACON pg 87
A unit hit by a Narc beacon will not suffer damage from the Narc itself, but will suffer 1 additional point of damage from any Indirect Fire (IF), LRM, or SRM attacks for the rest of the game—unless the unit is within a friendly ECM bubble.
So looking at all of that, this Raven RVN-4L running under active STL would, under my current understanding:
1) Not be able to use it's PRB due to being effected "by a hostile ECM" i.e. itself
2) Can't actually use it's ECM in the friendly manner since it's running the STL (currently in this example, without turning it off)
3) SNARC doesn't seem to be affected in EITHER of the two cases of
a) The Raven shooting it's SNARC at a enemy since the STL "hostile ECM" only affects itself not any enemies (or friendlies for that matter) and the SNARC is only stopped by an ECM bubble friendly to the targeted unit.
b) an Enemy's NARC wouldn't be hindered if it hit the Raven either since the Raven's ECM is hostile to the Raven. The Raven would have to turn off it's STL and engage it's normal ECM
edit: also for a unit with IF and STL, i.e. BattleMaster BLR-4L, being in active STL shouldn't prevent it from taking advantage of a friendly NARC attached to an enemy correct?
Do I have about the right of it? As an aside the only other downside to STL that I can find is participation in a C3 network would be impossible while active?