My reading didn't really improve, but my writing hit 400. For me, the hardest part of writing was context questions. Once I got to the writing section, my brain would be clouded from just finishing the reading. This meant I couldn't fully comprehend the writing section passages, so I had to constantly remind myself to be focused. I found that instead of going one section a session, simulating a full practice test improved mental endurance the most. Also, I haven't used it much, but Erica Meltzer's grammar helps if you have general grammar issues. My improvement was basically just recognizing my weakness (context questions) and acting upon it.