Gmatclub CAT tests

I have used GMAT club test for my preparation. The Quant test is difficult than other Quant tests available. The level of difficulty and the questions are similar to what is tested in GMAT.
Since the answers provided are by the club members, all the approaches to a problem can be seen. The mistakes done by you and others and the correct approach does indeed help to clear the concepts.
The above approach to explain the answers is applied in the Verbal tests too. But the arguments proposed in the explanation of a problem by club members can be confusing. The approach will work well with Quant as it is pure mathematics but the same may not be the case with Verbal which is based on interpretation of data.