For the uninitiated,GC is GMATClub - The forum right here were you are posting your questions expecting a good answer.
BTG is "beatthegmat" - A reputed test prep similar to GC, but having many more experts...
Both send out questions daily by email if you subscribe.
Also there are 25/30 GC Maths tests and 6 Verbal GC Tests at http://gmatclub.com/tests/
And again, which Verbal tests from third party publishers do you recommend?
I don't want to study material that contradicts the OG or has unclear answers..
Yes there are materials that contradict OG, but for Quant it is always better to check other sources...
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