sam2304 wrote:You are looking from the perspective of a 700 scorer. A 700 scorer will hardly have weak topics to hone and a 600 scorer will have many weak topics to work on. You can finish reviewing in a day because you have said that the problems in the books are too easy, but it is not the same case with a 600 scorer. A 600 scorer needs more time to first learn the concept, apply it on few problems and get them right. I don't think its quite easy to do all these in a single day or even 3 days with many weak topics to work on and frequent mock tests are useless unless you make a considerable progress from your previous test. I increased my quant score from 43 to 49 by working on inequalities, work rate, geometry pblms and it took me a week to learn the concepts from MGMAT, solve related OG problems, review them and then again apply them in practice tests. Solving the problems in practice test wouldn't have helped me by any means, I would have known only the solution to that particular problem or the formula, tricks involved but no way I could solve another problem which involves same topic. That may work for people who are already good with the basics but not for beginners. Same is the case with verbal and believe me it takes more time for a non native speaker to improve verbal part.
Definitely not trying to instigate an argument with you brother, but my philisophy is - you train how you fight.
I think most people will get lulled into a false sense of security by GMAT books because they can solve the problems with an unlimited amount of time, and the questions are generally not of higher difficulty. For me personally, I really struggle with the complex terminlogy and strategies that the books try to teach. I formulate my own and use my own.
If there's a problem that I'm constantly struggling to solve (for me, it's usually combinatorics), I can attack those aggressively until I familiarize myself with them and develop my own course of action on how to solve them.
I'll be honest though, with the books on the market, I struggled to find ones with sufficiently challenging combinatoric problems in sufficienct quantities. That's why I trained with practice tests. As soon as they adjust to your ability level, your mind is constantly challenged with tough problems and curve balls, and tougher combinatoric problems are more likely to emerge.
The first GMAT CAT I ever took was from a Peterson's book. I scored something like 610. For the two months before game day, I completely abandoned books and was taking 4-5 CATs a week. When I wasn't taking a CAT, I was reviewing my old CATs and solving the questions I got wrong (again).
Some books are really good though. I credit Manhattan GMAT Sentence Correction for single handedly boosting my verbal from the mid 30's to the low 40's.
I will caveat with this - my strategy is for native speakers. As someone who was raised in one English speaking country or another for most of my life, I have an inherent advantage with verbal. For a non-native speaker, verbal will probably be a much more significant challenge than what I experienced.
"Never doubt that a small group of thoughtful, committed citizens can change the world. Indeed, it's the only thing that ever has" - Margaret Mead
I have taken two tests so far.. One from GMAT prep and the other from Veritas prep.. Both times I scored a 590.. 
