Quote
So what is that which we recieved when a person get born again?

New life by the power of the Spirit of God.

Quote
Do we get a new incorruptible seed, or not?

The "incorruptible seed" is the word of God (I Pet. 1:23). We do not "get" it, but are reborn by it.

Quote
Does everyone remain the same so a sinner doesn't need a brand new spirit?

If the sinner gets a "brand new spirit," what happens to the old one? And why not also a "brand new soul"? You're adding to Scripture. The spirit of the believer is REBORN, not replaced. But that does not make the believer's spirit infallible.

Kyle

I tell you, this man went down to his house justified.