My Gynae is very funny, I asked him about stretch mark cream. He asked me "Do you know why are they so many different brands of stretchmark cream in the market? That is because none of them works!" He told me using olive oil is good enough, whether you have stretch mark or not, it's all in the genes. But he did mention before that cocoa butter may cause irritation to the skin, so better don't use.
I didn't use any stretchmark cream for my #1, only baby lotion and baby oil, and I didn't have any stretch marks. Hopefully, I don't get it for #2.