Cherry-picking a verse from Paul won't help you on the day of judgement.
Notice he says "with the heart a person believes, resulting in righteousness".
True.
..but it doesn't mean we are no longer sinners.
We all are .. some more than others.
If you want to believe that you will go straight to heaven without question, that's your prerogative..
I certainly don't think that about myself .. or anyone else for that matter.
I think, that just as in this life, we will be brought to account for our misdeeds in a court of law, we will have to answer to the Most High in the next life.
Of course, G-d can forgive whomsoever He wills.
..but isn't it strange, that you think you are guaranteed heaven, just because you believe in a certian creed .. whereas you think that others, who have a different creed .. such as Jews and Muslims, are not so fortunate.
I'll leave it all up to the Almighty.