Airtel 256kbps speed broadband good for wifi connection?

i have airtel broadband of 256kbps speed i want a wifi connection but my brother has mtnl connection which gives him uptp 2mbps speed in wifi in a connection of 512kbps speed should i go for mtnl or stick with airtel if airtel what will be its speed in wifi then
i am using airtel 256kbps speed but in mtnl in the same plan also 5o bicks less they provide 512kbps minimum speed so i shoul opt for mtnl or airtel tell in regard of wifi connection!!!!