Did not seem difficult at all, however got 18% and failed on it after a month of learning on trailhead getting up to 75 badges and 1 superbadge before taking the exam.
Things I noticed, before I took exam I watched https://www.youtube.com/watch?v=lIZk8cKOFHk&t=6613s the person teaching is teaching in classic while a lot of trailhead is in lightning. He did help me visualize a  few questions on the test I would've had no clue on.
Things I would recommend studying is going to every profiles, user, permission sets, validation rule, object and flow and look at what you can and cannot do, and the default settings.
In object such and such pick 2 of 4 things you can do. In this thing what is true?

I'm thinking about retaking it in a week, its a good test, just wasnt ready for that. Thought it would be more scenarios rather than 'what are your options, what is default settings, what went wrong, what things could have not been done right'. It will get you if you are a second guesser or overthinker because you have a lot of options, a lot of questions I noticed you have to pick 2 out of 4 choices, meaning 2 times to second guess yourself in 1 question.

Definitely not easy, but felt like I was closer to passing score of 65% or around there, I felt like I had small chance to pass before hitting the submit answers. I had feeling I did have a feeling I wasn't going to pass before I started the exam but I took it anyways because I kept seeing the message "FAILURE IS AN OPTION". So I'm not too upset I failed, but disappointed. 

I'd say my reason for failure was that I was having too much fun in trailhead rather than specifically studying for subjects relating to ADMIN exam. I had over 35 minutes left after answering questions and went back to check answers too for 20 minutes, which I felt good with, but all in all, 18%.

My 2 cents. Good luck to anyone taking it, also look at the flashcards, I didn't look at them but now thinking I would've passed it if I did http://www.sfdc99.com/2014/10/02/guide-to-passing-all-salesforce-certifications/