Hi V-Rap,
I'm not an expert since I haven't taken the real test yet. But this is what I am have found:
800score's quant is too involved to finish on time and their verbal is too easy.
The Veritas Prep questions on the quant are questionable. Some of the questions just don't seem right and nothing like I've seen in the OG.
You should have also gotten some Arco tests...not perfect either, but prob the best of the three.
I didn't think the Veritas Prep course was that bad. I do wish that I completed the Official Guide before taking the course. Also the questions in the beginning do hold more weight. If you have already started the course you know what I am referring to when I say that.
RC: I think you have to develop a method that works best for you. I actually read the passage twice quickly.
The GMATsets are great. the questions are challenging and feel like questions that would be asked on the test. (again, speculation since I haven't taken the test yet) Someone on here should have them. Too bad I didn't discover them earlier.