GRB is a good book but as with other MCQ books, is associated with multiple wrong answers. Secondly difficulty level of questions are high.
I will personally recommend you to go through NCERT not only for biology but also for physics and chemistry. Rather then going for variety of fancy books, arrange modules and question papers of Aakash / Allen or both and do them carefully. These have good standard MCQ with minimal or no errors. Standard of questions are also up to NEET level.
One step ahead you can go for online test series of these institutes to assess your performance Nationally as majority of students either join these institutes as class room coaching or online test series.
Thanks and Best of Luck