There is no fixed institute that can guarantee you the best results.

There are students who had cracked IIT or NEET by studying themselves. AKash is a great institute  and if taken help and also proper guidance can help you crack NEET but it will always be upto you to perform in the grandest stage.

Their mock exams have been known to be very helpful. So if you even ignore the classroom, please go for the mock exams.

All the best!