I have had Sify for some time (almost a year).

I stay in Chennai and was originally in one area and have shifted to another. I have had Sify for some time (almost a year). While in the first house, the connection was surprisingly good. Unfortunately the connection in the new house is not good.
The first connection was a 64kbps connection (no comments please, it worked well for browsing) and speed tests showed a stable 57-61 kbps over a couple of weeks. Minimal connection troubles if any. The installation was strange. They had promised to come on one day and didn’t show up, so we called them and then they came the next day. Like Sushubh has said, the wireman did everything and worked on the basis on “these numbers in those boxes” but managed to get everything running fine. I was immediately happy with the connection.
The second one was also 64kbps. It gives only around 40kbps on speed tests and is very reluctant to connect properly.
Like Chinmoy Mitra says, it depends on the area you get the connection and the last mile local operator.
The best thing to do is to ask people in your area how their connection is and then get the same one. That way you won’t have any unpleasant surprises.
I have a sneaking suspicion that the Sify dialler actually causes troubles with Windows. I am quite good at maintaining my computer and the only times it has given trouble were 1) strangely, once after an automatic update and 2) after getting the sify connection. I solved the first one by a fresh re-installation (uninstalling the updates didn’t help :-( ) so the second time had nothing to do with the first. The problem after sify slowly crops up and gets worse week by week.
Does anyone else have any trouble due to the dialler, any new problems in Windows?
Before Sify, I was using Iqara. Service was good, connection uptime was average but the speeds were terrible. However, they didn’t use any fancy dialler, just good ol’ windows networking. Setup the connection through XP, no trouble at all. Connects quickly (when the network is not down). Why can’t others do the same ?