Bring your Opinions and Facts! need help w/ ps2 disc?

I got a few games with pretty good scratches on them. My ps2 plays other games with minor scratches pretty good so im sure its not the famous eye problem. I tried the toothpaste trick on my San Andreas disc and didn't work. i tried it several times. I used white toothpaste non gel and let it stand for 5 minutes before washing it off. It seems it only made it worse; I hear alot of controversy over this trick and i think it dosn't work. A little over half says it dosn't work, while the other bit says it does. I gave up and i'm just going to take it to Gamestop to rebuff it. Any tips here are appreciated.