Ok, I have a few gripes to harp on:
Psychic gives things like Tyranitar, Metagross, Weavile, etc...a free switch in. All of these can OHKO Latios with a CB attatched:
Crunch vs. 4 HP/0 Def Latios: 175.50%-207.28%
Meteor Mash vs. 4 HP/0 Def Latios: 110.26%-130.13%
Night Slash vs. 4 HP/0 Def Latios: 129.14%-152.98%
Dragon Pulse hits more things for neutral than Psychic, and the only reason to use Psychic is for things like Heracross or Infernape (only the former proves to be a pain). Dragon Pulse does more damage to everything bar Fighting and Poison types.
Eh, maybe it's just me, but I'd never use Psychic on any Latios. It is strong though, I can admit that. But most of the things that switch into Latios (Weavile, Tyranitar, Metagross, etc...) are all hit harder by Dragon Pulse (Psychic doesn't even hit Weavile/TTar).
Psychic has its uses, but when using it, you're taking a big risk.
Again, I'm going to strongly disagree here. If you read the sets I suggested, the only reason why I mention Psychic as the 3rd or 4th attack option on Latios' sets are because it HELPS its coverage. You shouldn't ever be spamming Psychic immediately on a Choice set. You can talk about how bad of an attack it is in terms of coverage, but did you not miss how the first two moves on the set hit EVERYTHING EXCEPT EMPOLEON for neutral damage. So why would Psychic be "hurting" the set at that point. If anything, you can score some super effective hits now, since neutrality is already covered. The all-out-attacker is using Dragon Move / Surf / HP Fire / and Psychic, because the first three moves hit everything in fucking OU neutral. I hate to sound defensive, but there is a good reason that I suggested Psychic in the first place. Your statement about Dragon Pulse doing more than Psychic is also false, as they have the same base power. I don't think it's a risky 3rd or 4th option at all.
Originally Posted by Jibaku
Firstly, if you choice them they become Pursuit baits in one wrong move. This becomes even more apparent if said Pursuiter has Choice Band, as they can't really Trick their Choice items without getting severely punished. Tyranitar does its job very well at doing this, and also serves as a universal Lati@s counter. The thought of Specs Draco Meteor is absolutely horrifying, though, but in the end Tyranitar will win even if it switches into them as Latios' SpecsMeteor does <50% I believe to Max HP/SDef Careful TTar. As their Special Attack fall, they're incapable of OHKOing Tar in two turns later and promptly gets 2HKOed by TTar's own Pursuit. Scizor has access to Roost and is able to shrug these hits like they're nothing, while its Pursuit drives the twins away. If they have HP Fire, they're at risk against Tyranitar or even Snorlax switching into it. Specs Surf can be devastating to both TTar and Scizor, though (the former takes less than 50%, however), so be prepared to switch in and out like mad. Think about it as SpecsMence...except with more power and Speed, but has a weakness to Pursuit. Bronzong can take a Draco Meteor and Hypnosis/Stealth Rock/hurt it with Gyro Ball/set up a Screen, etc. Oh, and Blissey walls them, but beware of Trick!
Maybe you should do damage calcs and there is also a good justification to actually use Modest over Timid. For starters, Gengar is going to be scarfed and beat you anyway, and Infernape really can't do shit to you. That leaves you only having to worry about Salamence and Flygon. So you have to ask yourself, is beating the rare Jolly varients of them worth the 10% power drop? How about this:
Modest Choice Specs Surf vs. 252 HP / 216 SpD Careful Tyranitar: 42-49%, that is an 87.5% chance to 2HKO with Stealth Rock. I would be very careful about switching Tyranitar into SpecsLatios. Also, If you do run Maximum Special Defense, you may survive but now your Pursuit does: 67-80% meaning Careful Tyranitar is not a "counter" by definition.
Furthermore, Scizor doesn't make a "great" switch in either:
Modest Choice Specs Latios Draco Meteor vs. 252 HP Scizor: 65-78% 1st hit, 32-39% second hit. If you want to bother switching into Surf, then a Modest Choice Specs Latios Surf will do 60-70%.
So the mention of them as generic "counters" is not the best description. Nevertheless, they are fantastic checks in their own right. I mentioned Choice Specs Latios as the most popular set because IMO it is by far the most powerful, and Draco Meteor + Surf hits all but 2 pokemon for neutral damage, allowing use Psychic if you please to score some super effective hits.
Scizor also doesn't appreciate switching into CB Earthquakes either, as they do 41-49% with an Adamant nature, which is a 60% chance to 2HKO with Stealth Rock.
My favorite counter right now is Bronzong, specifically CB Bronzong as it can survive 2 hits from anything Latios as and retailiate with Choice Band Gyro Ball. There are plenty of checks for these two though.
Originally Posted by Jibaku
Dragon Dancer's got a boost with Outrage. It still doesn't like Tyranitar, though, so it must predict TTar's incoming or die as DDed LO Quake doesn't OHKO the rock titan.
If you would like to leave your Max HP Tyranitar in against my Adamant Latios to take 90-106% from a Dragon Danced Life Orb Earthquake be my guest.
Originally Posted by Jibaku
I'm also pretty against Psychic on Lati@s simply because of Metagross, Scizor, Weavile and Tyranitar.
Again, Psychic is by no means a poor option on Latios, who has the movepool to dispose of all four of those pokemon. Never would I use psychic on my first entrance into battle, but at the same time. You shouldn't be spamming your third attack anyway, but it helps against Heracross who can Pursuit or Megahorn the fuck out of you, or Machamp, who can survive Dragon Pulse and confuse you. Again, you lose no coverage.
Originally Posted by Rai
There hasn't been much talk about HP fighting which is kind of surprising. Dragon/Fighting has near perfect coverage, arguably better than Dragon/Fire. Even a completely unboosted HPFight can 2HKO alot of common TTar spreads.
Latios' 252SPA Timid HPFight vs 252HP/4SPD Ttar: Damage: 51.73% - 60.89%
That's because HP Fighting sucks. It 2HKOs Tyranitar, but Surf does also. Furthermore, your stuck using a piss-weak attack against Steel Pokemon.
Originally Posted by Peachfuzz
That doesn't stop Scarf Gengar, does it?
Scarf Gengar has a move that OHKOs [most] Tyranitar and Weavile.
Originally Posted by Mien
Yes, SR is the reason why Specsmence isn't that popular anymore it simply kicks 25% of it's health any time. For this it can only switch into EQ or if another pokemon has died before because SS/Hail +SR add damage to much. Choice users all are about Hit and run but if you can't switch in much the choice user loses it's effectiveness
Specsmence isn't popular because it has absolutely no way to get by Blissey, not its SR weakness. Specsmence is still stupidly potent.
I probably should put this in the OP but its not necessary. My stance on Lati@ are that they are VERY potent and helpful members of OU, but not broken. I know from experience using them in MDWL preparation and the tournament (they are a lot more fragile than you would think).