I know this is an old post, but I'm replying so that anyone who looks up ATI on the site can read this, too.
When I first started working on the ATI, it seemed pretty hard. I was scoring in the 60's on my practice tests. However, I've been keeping up with my practice tests and reading the focused reviews that ATI provides. Now, I have been scoring in the 90's on my practice AND proctored tests! The questions seem very easy to me now.
To anyone who is doing the ATI or any other kind of NCLEX review, just keep practicing and be consistent in your studying. I promise that the questions will start to seem very easy and you will pass without any problems! Don't worry so much about how hard it will be, just use the reviewers how they are meant to be used and you will start to get so good at it!
I will be taking my NCLEX-PN in a couple of months and I feel confident that I will pass! Wish me luck, everyone!!