Ever Since the launch of 3G I have moved to it. Currently I use 3 BSNL 3G connections, one for phone, USB modem and also iPad2 (micro SIM), it works fine all the time even on travel and I get 1.2 Mbps consistently in the past 3-4 months. Other than that, I have 2 Photon + connections and both have great speed inside the city, giving me 2Mbps. Apart from this, there is also a BSNL wired connection as a back up which hasnt had an issue in the past one year or so.
Was using Airtel at Mangalore and they have very good connection and reliable speeds, but in Kochi they have limited area covered. Previously used Tata wired, but as Binny pointed out, it goes out whenever it rains and the CC was pathetic.
Regards
Nirmal