Ok, first of all, I have to disagree with the statement that a pokemon needs 100+ base offensive to do decent damage in OU (Arctic, if you really believe that, you are a moron). I think the perfect anti-case to this is Sub-Boah, who can even perform extremely well with Modest, all-special f-thrower/ice beam/dark pulse. Not only does this boah destroy common switch ins like Steel Types, Heracross, Breloom, and even has a chance of killing relaxed swamperts (they could very well get killed if they switch in on dark pulse or take a turn to sr, or get flinched), but it easily sets up on weaker special attackers like Jolteon, and destroys Rotom-A (who never switches out fearing pursuit, and always takes a turn to reflect/w-o-w only to get blasted by dark pulse).
Also Sub-Tar destroys Blissey if it has focus punch, and even without focus punch Blissey can do nothing to TTar's massive special defense, superior speed and 101 subs. TTar can stay in and fight until blissey has to heal, and then switch in a fighting type teammate on the heal-turn. If Blissey lacks seismic toss, TTar can even pp stall it to death (Obi's Toxic-fthrower-wish-protect blissey always loses 1 on 1 to sub-ttar, even without any physical attacks).
Also, relaxed pert commonly carries special attacks. The point is that you don't need a monster special attack stat to hit hard in OU. However, if you do use a 95- offensive stat you need either a ridiculously powerful move (like explosion), or you need to play at weaknesses, especially weaknesses of common switch ins.
I'd agree that metagross probably needs HP Fire, and maybe Grass Knot for swampert. Also, how is this a set if you've listed 3 different items for it? -.-
Anyway, there was my blurb on using weaker offensive stats, though I doubt special metagross would ever be as good as special TTar, as 101 subs really do make a difference with that pink bitch around.