I just realized I forgot to post this.
Got it day one, naturally. It's the reason why I still haven't finished MGS3 or even started Kirby and the Forgotten Lands.
20 hours in and I'm just about at the end of Act 1. It's really good but goddamn, this game can be a motherfucker at times. I considered dropping it a few times already but so far I've been able to push through each time. It helps that bosses rarely bottleneck you, there's usually something else you can go explore instead of banging your head against the wall.
Usually. I think I've done just about everything I can at this point, so tonight that fucking boss is basically my only option. At least it's a "fair" boss.
The only thing I've encountered so far that I feel is truly bullshit are bosses that can summon regular enemies. As far as I can tell, the actual summons are random so it can really fuck up an attempt that was otherwise going well. Made it to phase 2? Sucks to be you, asshole. This boss just summoned a couple of flying enemies. So now you have that extra bullshit to deal with! I stopped counting how many times I died solely because of the fucking chaos that ensued when a boss summoned a couple enemies that started going apeshit. Only to succeed on the very next attempt because he somehow didn't summon anything (or summoned something more manageable). It adds an element of randomness that really fucking sucks when you're trying to learn a boss' pattern.
That's my only real complaint so far. The game is really good once you get used to its difficulty.