I bought my original 'fat' PS3 launch model back in 2007 in Belgium (aka PAL), and have been playing burned DVD5s, DVD9s, fanedits, etc.. etc.., both in PAL and NTSC format. Never had an issue anywhere. Not with any single disc.
The only thing I do is burn all my DVDs through Nero Recode, because for some reason DVDShrink doesn't recognize my Nero installation anymore.
Not that I care, since Recode works fine.