So yeah, after thinking for a while, I guess imma shoot my opinions in.
There are two common sets for Durant, one being the Hone Claws set and another one being the Choice Banded set. In my opinion, Durant isn't that hard to stop if you know the set it carries. But the biggest problem is, you'll never know whether if you're opponent's running a Choice Banded set, Hone Claws set, or to a lesser extent, the Choice Scarfed set. Example: Alomomola switches in, expecting a Choice Banded Iron Head, but instead, Durant Hone Claws up, and proceeds to deciminate it. Ok lets have another example: you're having TrickScarf Uxie versus Durant. You're expecting tim to expect a switch and Hone Claws up, so you trick'd him. But then, it turns out he's Scarfed. Congratulations, now you have a dead Uxie.
Ok, the so called "counters" listed by people above includes:
So here. Ok so, Qwilfish. Qwilfish isn't a counter to Durant, at all. Yeah it counters the CB set pretty well, but not the Hone Claws set. Durant just wouldn't give a fuck bout the Waterfalls Qwilfish fires off at it. It can pretty much set up on it, as long as Qwil doesnt carry Haze, that is.
Same as Qwilfish, Gligar wouldn't be having a great time dealing with Durant either. Despite having around over 500 defense, Gligar still finds itself struggling against Durant as +1 LO Iron Head has a decent chance to 2HKO it, and with rocks up, it's a solid 2HKO.
Not much to say here, but some variants of Durant carries Thunderfang, so Poliwrath wouldn't be considered as the safest counter.
Not a counter at all, it's only a check. There's certainly no way of switching it into Durant, as CB Iron Head always 2HKOs it. Hone Claws Durant might be easier to take on, but 30% chance of flinching wouldn't be cool, at all. Oh and, in order to check Durant, you'll need Fire Punch as Head Smash doesnt have reliable accuracy to be classified as a check, and imo having Fire Punch on Aggron is just a waste of a move.
Now, this thing is a real counter to Durant, at least to CB and Hone Claws variants. The only variant it has trouble against is Hone Claws + Baton Pass variant, as it can passes to whoever when Magneton switches in, sometimes with even boosts already.
Only mon that can take everything Durant throws at it, and Dtail it out.
Will edit in checks later.
With nothing other then Steelix and Magneton being able to switch in safely against Durant, in my opinion it's broken. Yeah, it has checks, but did having checks stop Excadrill from being banned from OU? Or even Staraptor from UU? Or Porygon-Z from RU? So yeah, that's it I guess, feel free to say me wrong.
I'm back :)