Whirlwind Zapdos is a demon if it has Spikes. it isn't quite as bulky as Raikou, but man, I just love the shit out of Whirlwind Zapdos. you can even run Rest-less with TW/DP/WW/TB and just switch in on Skarmory all day. it's so awesome.
honestly, though they are so good, I don't consider Zapdos/Raikou the most intense Special threats. they're just lucky that Electric is SE on 2 of the 3 most popular types, but neither can force an issue with another Raikou, which we've already concluded is "the other awesome Special absorber," much less force an issue with both Raikou AND Snorlax.
here is where I consider a few other things--Exeggutor in particular--better as a Special threat. Snorlax and Raikou (who've been on just about every hypothetical GSC team lately) can usually always switch into Zapdos or Raikou--not quite the case with Exeggutor. I think to be a Special threat, you have to be able to actually be a threat to the Special walls.
if we factor in BP Growtheons, the problem that Raikou and Zapdos face doesn't really get solved--Thunderbolt still isn't going to do much to another Raikou, and here is where other Special attacking threats plunked to the UU/BL tier (Moltres, Houndoom, Jynx, Alakazam) join Exeggutor in having the advantage of a strong STAB attack that hits both Snorlax and Raikou for neutral damage.