Aristotle is difficult to read, for a number of reasons. The main one in my opinion is that it is so dense of inestimable content that I am overwhelmed at every paragraph.
However, I always make the decision: better getting the gist of it and if, possible, reread later on than stopping too much the first time.
Of course, it goes with personalities, I know.
I have read the Ethics. Tried the metaphysics and simply could not, though.