He is ripping you off. He is dodgy and cheating you. Discs don't wreck PS2's, s*** soldering and lame chips do.
Now he wants you to pay more? WTF? He did a crap job to get more money out of you.
And HELL no, I have played my PS2 for 8 hours straight. I have played THOUSANDS of hours on it. Works fine.
Use a good chip and good media (ritek, TY, verbatim) and a good burner (pioneer 106). The word "problem" will be unheard of