Hi national01,

The best predictor of how you'll perform on the GMAT is to take a FULL-LENGTH CAT (with ALL sections) under realistic and test-like conditions. The more you deviate from that 'standard', the less likely your score results are to be accurate.

While I have not personally used the software that you've mentioned, it certainly sounds like it gave you a result that wasn't necessarily accurate. There are so many different resources that you can use during your studies that if you don't believe that one particular resource is proving useful, then you can easily choose to use a different resource.

GMAT assassins aren't born, they're made,
Rich