

You can always use GMAT Prep tests to see how you score on official tests and meanwhile you can challenge yourself with the Veritas tests. Now you have a way to see what to work on to get that higher score you seek. In other words, there is room for increase in both your quant and your verbal section scores and the Veritas questions may have in a way highlighted some of the flaws in your processes or gaps in your skill set. There is much to be learned from the Veritas questions, and so my suggestion is that you use those test results maybe less as indications of your overall skill level and more as resources that you can use to assess what you can work on and as sources of things you can learn. I have seen this happen before, and it happens even though many people score almost exactly the same on Veritas tests as they do on official tests. So it's likely that in taking the Veritas tests you have been thrown off by the differences between what you have seen on those tests and the questions you have seen before.

To answer your original question, Veritas quant can be subtly more difficult that official quant and the verbal questions on Veritas tests are subtly different from the questions on official tests, while Manhattan questions are also subtly different from those on official tests, but in a way different from how the Veritas questions are different.
