I had the same experience. Guessed on two questions total. Got answers on all the rest. I felt it was easier than the SMS practice test and about on par with the NCEES test.
I purchased this exam study guide from
http://www.engproguides.com/hvacguide.html
And so far its been awesome. Easily worth the $35 dollars. I will be purchasing his practice exam as well and a month or so.
On the Ashrae books. I have a few older ones. How much difference are the ones now verse the older versions? Should I buy new ones?
Also, has anyone taken any of the review courses? I plan on signing up for one soon.