TATA Indicom Broadband Download speed is low

Hello

I am using TATA Indicom internet from last 2 months in that i am getting less then 20 kbps download speed. I am in 512 kbps plan. i complaint about same issue they told me that this is 20 to 25 kbps is average download speed. I don't think so i think at least 25 to 30 kbps average speed is ok on 512 kbps plan.

I am using Hathway internet 512 kbps speed in that i am getting 25 to 30 kbps speed while downloading. some time more then 30 kbps.