Five for $25 sounds like cheap parts to me, but this kind of op amp would only be used in the better players, typically in the $3K range and above, so they are a significant improvement over the stock ones. It took about five minutes of warmup to begin to hear the difference. I'll leave it on repeat all night, but already there's an improvement in the separation of instruments, L to R and F to B, within the soundstage. With the op amp upgrade this has become a seriously good CD player which I would recommend without reservation to anyone considering an upgrade from a mass market player or from an older mid fi player.