Hi MikaelD,
If you find that your quant score is not improving, you may consider doing some focused quant practice, to find and fix your remaining quant weaknesses, prior to taking any further practice exams.
For example, if you are reviewing number properties, be sure that you can practice 50 or more questions just from Number Properties: LCM, GCF, units digit patterns, divisibility, remainders, etc. The results of that practice will help you determine your weak areas within that topic. Once you find and fix your weak areas, then move on to the next quant topic.
To help diagnose your GMAT quant strengths and weaknesses, I welcome you to take my free
37-question quant diagnostic. After completing the diagnostic, you are provided with a detailed analysis of your proficiency level of all GMAT quant topics, as well as an opportunity to discuss your diagnostic results with me or another TTP instructor/coach.
Once you feel you have improved your GMAT quant and verbal knowledge, begin taking practice exams to track your overall progress. When taking practice exams you may consider taking the exams offered by GMAC, since those exams have an accurate scoring algorithm and contain retired questions from past GMAT exams.
Please keep us updated with your prep and, if you have any further questions, feel free to reach out to me directly.
Good luck!