I've bought the first spindle I came across in some cheesy electronic store. The guy only had "Platinum" discs. They looked very cheapo, but it was at the end of the day and I really wanted to try SSBB that night.
Well, it turned out those disc were pretty good, as I have not encountered one single error or lock up.
The game is INCREDIBLY AWESOME!!!! I already love it just as much as Mario Galaxy
Memorex DVD+R has always worked for me, pretty much for all tasks.
I've heard a lot of good things about Verbatim on this board until now, but it's a cheaper brand. I found a 50 dvd+r pack of Verbatim for $17 today... I got it just incase you guys were right. Besides I don't have to use those for Brawl now, since I already used a Memorex.
it depends on a lot of factors.. for non-dual layers i have the best experience with tdk dvd-r's (but can't get a hold of verbatims easily so havent tried those)
but for dual layer discs it'll probably be different again