@Cik:
hell, it’s debatable if the ER is even in service (and it’s from the 90s, i think)
if you look at photos from syria the majority of the flankers you see still carry R27R.
No, ER is Flanker’s standard missile, widely used (at least under and between engines). Alamo is modular. U can change seekers (u need IR?, well just change it!) or extend engine sections according missions. A and C share the same seeker (there are seeker upgrades/mods of course, the same like aim9LMX), but C is longer and have aditional engine section. C is good and fine tunned missile (balanced but quite heavy), A is short legged (made rather for light Fulcrum).