PS2 Hardware

I recently bought a new slim PS2 thinking that years of revisions would only better its functionality, but apparently I was wrong. I'm getting numerous read problems. I've tried many games both new and used. Already 4 times while playing MGS3 the game would just freeze and even guitar hero would skip. I thought maybe it might be the lens and cleaned it but still does the same thing. I have come to the conclusion that it's just a poorly made optical drive. So I'll just take it back and get an old one. Does anyone know, factually, what the best PS2 model is?