I have been to RBI in South Mumbai, for ordinary person you stand in a queue for whatever time. I guess I stood around 15 mins once and 45 mins the other time. Generally you get one bag. The denomination is also decided by the mood of the teller at the counter.
45 minutes? Guess they have improved the service then.

But it it's only one bag per person, then it's not worth the money and time spent. For example, if I decide to visit RBI head office from where I live, I'll have to spend about 70-80 rupees on transport (including railway ticket) plus over 3 hours for two way journey by crowded train. Add to that one hour in queue. Grrr...
Few years ago when I was in Republic India coins, I got couple of bags of commemorative coins with the help of one of my relative. She was (is) in RBI and she happened to be in currency handling department at that time.

She even brought a bundle of Rs 5 banknotes for me, all for face and absolutely no efforts involved for anyone! I then lost interest in RI coins, she got promotion and became manager and transferred to old RBI head office.

She knows all the tricks dealers use to get coins, fancy number of notes etc etc...
Aditya