Is the Enemy AI good, bad, ok?

its actually decent/good they try to flank you.. so sometimes you simply can't sit there.

I think its better than the trilogy, but it's only apparent when you are fighting them in pre-scripted area like in narrow corridors as you did with ME2 and ME3. Out in the open they are laughably easy to get picked off with a sniper rifle.

In narrow areas they do support each other and flank you very often. In the open area where they can't flank, they just fall like flies.

I think they are pretty good, for the most part. Especially in Multiplayer, I find myself getting flanked and with the AI using surprising tactics. In single-player they do pretty well. Especially the Breachers from the Remnant that do their kamikaze runs. There is a good array of enemies that stay at range and ones that flush you out of cover. They do take cover as well, and better than in ME2-3, causing you to have to move around the battlefield to engage them as they don't just stick their heads out and wait to get shot in the face. Overall, the fighting is more dynamic than in the OT, causing you to use multiple tactics to get the best advantage. Compared to the OT, I think AI has improved in enemies. Compared to something like F.E.A.R., still not quite that good.

Really? They always hide behind cover and do not expose themselves when I shoot them from 200 meters with my sniper rifle, which makes sniping tough - as it should be. 

Nah, I used to use the Viper until I discovered that the Mattock with a scope makes an excellent short and mid-range tool that works for 95% of the encounters.
It may not be a 1-shot stopper but works really damn well as an all-around rifle that makes the sniper and SMG nearly obsolete.
As crowbar I'm using a scoped Falcon grenade launcher. Those two rifles plus an Asari blade is my loadout. 

Weird, in my encounters they always tend to stick to cover hard after the first shot, and they don't get out. If I'm shooting them from 200 meters and I need to use holdovers its really damn hard to make headshots, if I'm any closer I have to deal with surprisingly accurate return fire. I always shoot one of them and then flank them to get behind their cover to take another one of them out.

it's ok, some of the enemies use powers, some take cover, some will catch you off guard and surprise you, some are dumb

I find them as the best in the franchise. They can and do flank on you, which is awesome, just be careful where you place yourself in higher difficulty areas or you'll get screwed up. Also avoid being out in the open cuz they won't miss. I've been caught many times even with tactical cloak on when I move around the engagement. I also wouldn't advise reviving team members(at least if you have their attention or team member is out in the open, would help if I actually used the squad command to maybe limit that occurance) cuz that's just a good way to get killed to.

It's... Like the game itself. Very very good in some department: Fighting you if you play static ME2 style.

They're very bad if you use a sniper 100 meter away from them. Most of the time they won't even move.

AI for monsters are avarega but enemy AI... Man they are fucking ruthless it's very well done

It's OK. It does have its derp moments when snipers move out of cover, but most of the time it's serviceable.

And really, unless your AI is part of a scripted encounter, ''serviceable'' is the best it's ever going to be in a video game.

It's pretty good. The occasional charge up the middle by the big guy with the Gatling gun took me by surprise the first time. Dude has some serious shielding.