Offical cert guide practice exam close to the real thing?

Aside from the simulations, since there are none, how close to the real exam are the Pearson practice questions that come with the CCNA Security 640-554 official cert guide? They seem pretty easy to me but i might just be ready to take the exam.
Comments
i bought the Boson test, and I was not passing those, but I took the cert anyhow... I do think the Boson tests are harder than the actual cert test
CWTS, then WireShark