MB Superdrive + DVD+R DL = ??Errors?? Help!

Has anyone successfully been able to back up a DVD using a C2D MacBook with Superdrive and a DVD+R DL? I tried 4 times last night to backup some movies using Fast DVD Copy 4 and a new spool of Memorex DVD+R DL discs and every one of them got to 99% then pooped out. I thought maybe the application didn't like the discs so I tried to backup purchased iTunes content to the Memorex DVD+R DL discs and the same thing: about 90% the errored out. Oddly, both applications seemed to work fine when I tried again using cheapo DVD-R Office Depot brand media. Does anyone know if the Superdrives have a preference for a particular type of DVD DL brand or format? I'm getting the idea that just because the Superdrive supports DVD+R DL doesn't mean it works well with the format IRL. Any thoughts?
-Dave

Anyone?

So... everyone can burn DVD+R DL's just fine on their Mid-2006 MB's? Cool, just me then.

It appears that no one has tried using DVD+R DL. I know I have not. Have you tried other brands of media besides Memorex?

Well, Memorex DVD+R DL was the only brand of DVD+R DL I have bought to date due to cost. I tried Imation DVD-R DL and those seemed to poop out somewhere between 75 to 80%. I guess I'm wondering if anyone has had success with DL media in general (as a writeable media target). I write to both DVD+R and DVD-R all the time and the DVD+RW and DVD-RW media as well with scarcely an issue.
I'm kind of looking to see if maybe this is one of those features that is technically possible, but in practice not achievable on the latest Gen MacBook C2D's. If folks can write to any type of Dual Layer DVD media on the current generation MacBooks, please be kind enough to post here the brand and type/format of DVD media you used and the application and content you were successful in writing to the media. This would be a big help. Thanks!
Dave