Based on my experience I would not recommend ACT specially in Koramangala. I had to get my connection deactivated within a month after taking the broadband. The connection was installed and activated within two days on 27th May. Their billing cycle starts from 1st of every month hence I got a bill for 4 days, which I paid.
On 18th, the connection was not working and on complaining it got resolved only on 25th, after I sent a mail for disconnection. Remember that their minimum resolution time is 3 days but expect at least 7 days to 10 days.
Again on 26th, the service went down and there was no internet. I had no patience to wait for another week or 10 days to get the problem solved, hence I decided to go for disconnection to avoid another round of daily 2-3 calls to customer care.
It would be a foolish to take their 6 months plans or so. Get ready for premature disconnection and wait for refund which can take longer than the procedures of govt. offices