I had the opportunity to work with GMATBusters in the latter half of my preparation. By then I had already covered the basics from Gmatclub formula book and Manhattan series. Met him on the forums and later over WhatsApp groups and realized early on that he was very passionate about helping others with the GMAT math section. It was frustrating to be stuck around 49 and here is where the highly accessible help from came to my rescue. His experience with CAT (Indian form of GMAT but with a bigger syllabus and tougher questions) arms him with the tricks and insights that he is kind enough to explain with patience. I am sure that whether you are a beginner or stuck at Q49, his insights and help can give you that push you need to get to your desired quant score. It did help me in my journey. And that is why I recommend working with GMATBusters for your GMAT preparation. Thanks & good luck.