I had traded with Kotak for sometime but its like a trip to hell for short term trading. If your terminal stops working then god save you, the RMs dont pick the phone easily and even if they do its very difficult to get across message to them
Sometimes in case of real bad load it stop responding.. but recover quickly.
The day when satyam went to 6 rs then it stopped working till 10:15am in the morning. but I still manage to get my satyam at 7 with before market opening order.
If they can reduce brokerage a bit then its best a day trader can have.