I am planning to give my GMAT on 29th August. While in every other section, my accuracy is around 90%, my accuracy in Sentence Correction waivers between 40-80 %.

Taking the advice of a lot of people on this forum, i thought i would take the E-GMAT course but scored a 93% on their diagnostic test. Should i take the course anyway?

I am currently using Kaplan Live Premier for my preparation. Should i use anything else?