First raid, first downs! Hunters are awesome!
This tale begins with four hunters - Gold and Durendil, master soloers and tanks, and Helldz and Ottanøk, who knew how to use awesomeness of the hunter class to it's fullest, as dps.
One of them (he will recognize himself^^) was already linked to the Mogu'shan Vaults, so we flew to the Heart of Fear.
First up, Zor'lok. First try taught us that Mind Control was evil. Second try taught us that MC was evil and fast to come. So on the third try, we feigned death on the attenuation platform while calling back our pets, waited for an attenuation, and then burst him. We got him to 48% before the last platform, and after that it was bursting. We also had to help our fellow hunters survive the exhale.
Difficulty level: Pet tanking wasn't too hard since he stopped meeleing often, although he did two-shot pets. It really was a dps race.
Is he doable in 25-man? Yes, with 3 times the dps.

Then we went to attack Ta'yak. Now, this wasn't a dps race - so it was time to switch to 25-man mode. Which was the perfect time for dicovering that 25-man bosses hit about twice as hard as their 10-man version.
Our first tries taught us one thing: really hard but maybe barely doable, also known as "christmas" for us soloers. But it was just too close, pets died too fast and the debuffs targeted the same hunters too often, so we started doubting.
But then, in a flash of blue accompanied by the
battle.net logo, a hunter, named Shînîgami appeared, with her magnificent 540 pvp gear. Now, some could have doubted her importance, but this was a survival fight. And her contribution to the raid - applying the strategy with the same skill as everyone else - proved invaluable.
Try after try we perfected our technique: the secret was to avoid getting hit by his unseen strike - by putting all pets on stay and feigning death if you had aggro during the strike, which could get dangerous if the second on his aggro list wasn't a pet but a hunter, who could be caught by surprise - while not pulling aggro when FD wasn't available or wouldn't be available for the next strike if you FDed. Gold and me tanked, Ottanok and Shînîgami off-tanked whenever needed to give us time to rez our pets, and Helldz healed and rezzed those in need, until we got to phase 2. Where I totally never ever failed during the tornado gauntlet, so don't believe all you see in the video. Finally, the boss couldn't survive against such a perfect team (exactly what we needed to down him, no more, no less) and fell at our feet from overexposure to hunterness (and maybe, incidentally, his health reaching 0).
Difficulty level: Let's see: hits really hard on pet? Check. Could have been worse though. Some raid damage that's survivable only if you avoid everything else? Check. One-shot ability that isn't trivial to avoid? Check. So I'm considering him an all-around challenge, since he required both pet and hunter management, and we couldn't afford mistakes. Either way, if any of his abilities had been a bit more powerful it would have been a wipe.
Doable in Heroic? In heroic, he'd require more tanks, as well as a healing rotation for the debuff. So definitely more than five hunters.

Another hunter, Xcyte, joined us for the next boss: veni, vidi, wipi. Garalon's raid-wide damage was just insane. He wouldn't be doable with 6 hunters, so we switched to 10-man. Now, we could do this two ways: the strategic way, and the Leeroy Jenkins way. We settled for the "someone will take pheromones at 20 stacks but we won't actually assign someone" version, so it was a bit chaotic, but he still fell.
Difficulty: we had enough dps and healing to kill him without taking care of his fury stacks, so I have to consider him easy.
Doable in 25-man? Either we bring a lot more hunters, or a 10-man team could be enough if we calculated the best moment to switch pheromones and assigned a rotation to reset his fury stacks.

Finally, wind lord Mel'jerak blocked our way. We had some tries in 25-man, before realizing the sad truth: we needed 2 tanks for the boss, one for each blademaster, and another for the Healer and the trapper. That's 6 tanks. And then we needed dps on the adds too. So, sadly, it was impossible. We switchet to 10-man, trapped 2 healers and 2 trappers, Killed trappers, and then the traps on the healers broke. But everyone reacted quickly, no heal went through and once the adds died, the boss followed.
Difficulty: I'd say medium, since add management wasn't easy but we had more than enough dps and survival. If things had been a bit harder, we would probably have used an extra tank for the adds.
Doable in 25-man? As I said, we would need 6 tanks, and a lot of dps. So maybe 11 hunters would do the trick.
