They say a born Again christian is not a sinner even if they sin.

There are lots of Christians out there who believe their sins will no more count right from the moment they became a born again christian. Some pastors have been known to preach about it. As for me, a sin is a sin whether committed by a born again or not. What i believe in is that, God forgives when you ask for forgiveness by praying. And so, I believe it is wrong for any born again christian to believe God would not count their sins just because they are born again. What do you think?