Hi friends
I just purchased a 12v 5a  charger for 600/-.
I think its good price.
What do you say?

You mean 12v 5a Adapter. Right?
As long as it doesn't show any sign of voltage sagging, it's a good price.

Connect the adapter to the B6 and charge a 3 cell LiPo at full 5 Amps.
If you don't get Input Voltage Error then it means that the adapter is providing full 5 Amps at 12 volts and it's a good buy.