I did not find that at all. Quite the opposite, in fact. The highest I ever scored on a MGMAT test was 700 - score breakdown was 640, 700, 700, 670, and I ended up with a 740 on the real thing. Their quant is more involved - more steps to each problem, which makes it more difficult to do in the time allotted - and their verbal is, well, just kind of gnarly. The SC parts are clear, but the RC and CR sections I found to be rather more opaque than the real thing. In general, I would say that it is worthwhile to do the MGMAT tests and really focus on learning from your errors - the tests do give you a real workout in concepts, particularly in quant. In terms of how you will actually score on the real test, there is no substitute for the GMATprep tests
, and you should leave yourself time to go through both tests more than once.
...there ain't no such thing as a free lunch...