Very poor. 1st time the device works properly. 2nd time device cannot be read by PC or we get a warning message like "the device is disconnect or unavailable".
Not satisfied with this one.I have bought E 3131B through flipcart. On technical specifications it shows 21kbps speed.But it is not like that.I am using all sim cards like Aircel,Airtel,Reliance but none of these given speed net surfing.
