After doing the GMAT 3 times, I completely lost hope as I never crossed Q45.
Math Revolution helped me get a Q48 and I really appreciate that. Would definitely recommend Math Revolution if your aim is to hit the high 40s in Quant.
The course includes an account with all topics and especially focuses on a new DS approach which is fanatic and led me to achieve a DS score of 81%.
Hee is a fantastic tutor who is really patient and will help you out tremendously. Make sure you complete all of the work that he tells you to and if you do, nothing should stop you from scoring higher.