The only other gripes about Ninja Gaiden II are the recycling of bosses and fighting two different bosses back to back. The former isn't totally bad since you should already have a good idea of how to beat them, but it's disappointing in one of those "No, you should be dead already" kind of ways. As for the latter, this isn't necessarily a complaint about difficulty as it is about convenience. One of the worst feelings in the world of video games is to spend thirty minutes or so fighting a tough boss, only to realize that you have to fight another boss right after that without a save point in between. So, don't even think of turning off the system to go do something else. You're going to have to beat that second boss unless you want to have to go through the pain of fighting the first boss all over again.
It's these very moments in the game that caused GameTap to say, "You have got to be kidding me," but the aggravation only made the sense of accomplishment that much greater. And that is perhaps Ninja Gaiden II's greatest asset--not the pretty graphics or the gratuitous violence. And if you're one of those people sitting on the fence about this game because the original was so hard, don't worry. While Ninja Gaiden II is a difficult game, it's also far more forgiving than the original (particularly on the acolyte setting) and it gives you ample opportunities to beef up your skills and become a master ninja.
Pros: Excellent gameplay; nice variety in the later levels; great difficulty curve.
Cons: Story isn't all that interesting; camera can get in the way; few framerate hiccups here and there.