Oh dear! You don't want to be one of those people, do you?
What if you decided to believe in God? You would no longer fit into that category would you.
You might feel that those verses imply that you can't become a believer, but I don't think it means that.
Some disciples of Muhammad(peace be with him) were very staunch disbelievers at first, but later became staunch believers
In other places the Quran declares that Allah will know if a non-believer is pretending to believe - also with bad results. I think my interpretation is the most parsimonious, Allah has "sealed my heart".