Vajiram and Ravi is one of the most reputed institute for Civil Services Preparation. I took coaching for General Studies and Optional form there last year. It has excellent teachers who not only have a deep and thorough knowledge of the subject they teach but also are very helpful.
Don’t get afraid if you see a long line the very first day or for first 2 weeks. Make sure you find a comfortable place from where you can understand what the teacher teaches. Once you get settled, you will start enjoying the classes.