If you're trying to get DVDs for quality, it's a minefield out there right now. DVDs are drying up, good sellers are disappearing, and the remaining stock is getting older and more questionable. The risk of getting a DVD‑R goes up every year.
I've made around 75 DVD purchases this year and only received 3 DVD‑Rs total. Two of those were done cheaply - one wouldn't even play fully, and another was burned on a DVD‑5 instead of a DVD‑9, so the quality was noticeably worse. Only one of the three was "properly" counterfeited with matching DVD‑9 size and halfway decent pad printing, but even then it still couldn't match a real pressed disc. I'm not a collector, so I didn't mind that one too much since it's out of print and might not be obtainable in better condition anymore.
So yeah, sticking with reputable sellers is the best way to avoid headaches. But also give them a bit of grace when things go south - these discs are old now, and some won't be in perfect condition. Luckily, every questionable disc I've received that was a true pressed silver or red disc with a matrix code has still played fine, even when it showed heavy delamination.
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