Been using ACT for a month now. The connection is stable most of the times but sometimes due to some technical issues internet is interrupted. The most disappointing part about ACT is it’s customer service. There literally is no customer service from 6:00PM to 9:00AM. The only way to contact the customer care during these hours is via SMS service which they advertise when you call their helpline number. Emails are not responded to until after 2 days, so there’s no point writing one anyway. That said, in the last one month, I’ve had 3 incidents of no-internet which resulted in having to live 3 nights in total during the month without internet.
So, if you’re looking for a connection that’s super fast and are not much bothered by the above frequency of interruptions in connectivity, and live in a reasonably well connected area like Koramangala in Bangalore, ACT is just fine for you.