Depends on the bow you buy. Mathews stretch like the dickens, and so do hoyt and darton. However Bowtech puts the same strings on their bows that you would get after market so they don't stretch. They used to use winners choice string, but started making their own.

I think there are other bow companies that use quality strings as well. I can't speak for those though because I don't own them. Bowtech has always been known for their quality strings from the factory.

Paul