I have been using the same modem for about a year now, and for the past few days since I got my unlimited data transfer internet connection, I am surprised at the work that it is doing. Im downloading all sorts of stuff, and my computer is plugged to a 2 hour backup power supply as well, and Pondicherry not being a very bad place wehre power goes down for over 2 hours at a streatch, the computer and the modem have literally been running for over 2 months at a streatch now since july 1st when my plan changed to unlimited 512 kbps from 2 Mbps limited.
If you are outside India, you might laugh at this cos probably you might be on a 10 Mbps connection while reading this, but in India owning a 512 Kbps connection is like owning a Rolls Royce. I sit before this computer for about 6 hours a day, and therefore the AC runs here for 6 hours a day, and for the remaining 18 hours, the door is locked, and so are all windows, and the heat is almost unbearable when I enter the room in the evening after office. No AC, no ventilation, and all the heat that is released by the cpu and the modem have no means of getting out of the room.
Well, anyways, I am quite happy with the performance of the modem, as I know that the computer has to perform, after all it is a server quality cpu that I have got, and the monitor is always turned off, as I use it only when I am working on the PC. The modem is working in its full effecienty round the clock for the past 2 months, during which time it has not been turned off even once, and BSNL too has been able to supply data all this while (i think i am sure that there has been no downtime or anything), though at the office it is a different story.