I've only done their exams (not books), but their questions seemed different than the MCAT I took. It's not that they are harder or easier, it just seemed that the real MCAT asked for different things. The Kaplan tests are maybe a bit easier, by the smallest of margins, because they based their questions on the passage. On my MCAT at least, you needed to interpret data and extrapolate information more. I also had to know a few trivial facts on the real MCAT.
As far as difficulty, it's probably a good estimate. But as far as style goes, expect that the MCAT will feel different.