In theory, + media has better error correction, but the accumulated knowledge in this forum is that - media is your best bet. Many people have older DVD players won't play + media at all which in itself seems to be a good reason to stay away from + media unless you know absolutely the person receiving the disc has a player that will play + media.
As for the better error correction issue - that may be true when played in computer DVD players which need to implement high quality error correction so you don't loose critical computer data - but my experience has been that commercial set-top DVD players go 'on the cheap' when it comes to error correction, since they are designed to play commercial DVDs with low error rates. Many times here someone has said a DVD plays in their computer but not their DVD player.
I think I might've just gotten lucky
Sounds like it - did you run out and buy a lottery ticket? 😉