Countermeasure primer for those that need the help, this is an edited copy of a reply I made here on the forums trying to explain why one special performs better than the other so thats why its formatted the way it is.
I have included a pic of all 3 countermeasure
specials for comparison.
If you look at the stats for countermeasure range they are
both 62% but CML4 also has countermeasure reload of 20% and FLCS does not which
would make CML4 better for countermeasures because of the buffed reload so YES,
it will work better but ONLY for COUNTERMEASURES.
Now if you look at anti mort and anti missile range the CML4 is 77% and FLCS is 62%. This means CML4 can engage at longer distances thereby killing incoming sooner so with the exception of missiles you can get more shots at killing the incoming before it gets to you. This means YES, CML4 will also work better for this stat but ONLY for ANTI MORT and ANTI MISSILE.
Accuracy on both is exactly the same so it makes no difference in the decision. The only other things to consider are if you want weapon reload buffs or turret defense buffs. Keep in mind also that the turret defense buffs of 50% with FLCS will also make it more effective in bases against turrets and CML4 does not provide this additional protection.
Now to throw a wrench into this monkey. With the third countermeasure special, subaquatic, you can add that to either one of the other two to boost those stats even more. It can add COUNTERMEASURE reload of 50% and projectile speed of 25% to FLCS thus boosting its shortcomings against CML4 making up for its shorter range with faster reload and adding projectile speed which allows you to get more shots off. But, you can also add subaquatic to CML4 making its COUNTERMEASURE stats even better with more reload and adding projectile speed and thereby making it still better than FLCS with subaquatic in respect to COUNTERMEASURES ONLY.
Now here is the rub, COUNTERMEASURES ARE NOT ANT MISSILE OR ANTI MORTAR AND ANTI MORTAR AND ANTI MISSILE ARE NOT COUNTERMEASURES. They are two completely different stats that were introduced when subaquatic was introduced for gluttony, a long time ago. At the same time they changed the names anti missile and anti mortar to anti penetrating and anti explosive. You have to pay attention to the "antis" that you are putting on your ships to see if they are anti penetrating (missile), anti mortar (explosive), or countermeasure to make sure your using the correct specials with them.
You also have to look at the other stats that are there to determine which will be best for the particular use you are putting them in. If you are hitting bases FLCS is better than CML4 because of turret defense. If your are doing FVF or targets without turrets like scourge then CML4 is better. Then if you have room you can add subaquatic to buff either one of those further if you feel its needed.
For the detail oriented I know I may have skipped over a few things or possibly not explained them to your satisfaction so feel free to add to this as needed.