Well, i have played against Eldar Pathfinders and they kick
AP 1 on a roll of 5 or 6 to wound. Thats ripping apart most troop choices.
+2 to their cover save... Makes them dam near impossible to remove from a bunker / fortress.
Hits on a 3+. Wounds on a 4+ & Ignores armour on a 5+
Pinning.
well. need i say more?
On the other hand, 24 points per model. Realistically, you will only need 5. So 120 points of a mandatory troop choice.
Best if you avoid Close Combat - They dont really live to long in h2h
Yeah, they could be classed as 'expensive', but for a unit who is really hard to shift in cover (preferably sitting on a objective), they are a definate.