it costs about little as a starting item, ofc its bad. for 550 g you get 50 hp, 10 ap, more mana regen, an extra ward, and tribute no longer goes on cooldown when you kill a minion. that and the fact that you get an extra item slot makes it worth the 550 gold.
same goes for coin and relic shield
The sightstone combine items sacrifice item efficiency for slot efficiency. The ONLY time it would ever be useful is if you reach max items, but honestly on a support how often do you have the gold to reach full build?
Frost Queen's + Sightstone costs 3000g and is about 97% gold efficient, while the Eye item costs 2200g but is only about 83% gold efficient. The passives are the same save the one extra ward slot, so you're paying 800g for about 1100g in stats, one fewer ward, and a fantastic active.
I feel the need to point out that Frost Queen's is so good right now that some mid laners (Brand, Syndra, Morgana) are building it in mid lane. 40% slow for 4 seconds will catch any champion without a gap closer easily, and those champions (+ probably others) are great at CC'ing whoever the spooky ghosts catch.
Also, in general, sightstone items are weaker now because the warding totems all got buffed. If you have 4 wards every 2-3 minutes bot lane, you don't really NEED that sightstone first. I see most people fully completing their support item before finishing SS, as the totem + pink wards are enough to have vision on the bottom side of the map. The only reason I might rush sightstone instead is if I'm fully committing to roaming.
