I've been using 16X Memorex and haven't had any coasters, also have some 16X Verbatim but haven't burnt anything on them yet, are you sure the burning media is your problem?
There are other factors like, buffer too small, too many active background programs, AV auto protect running, the new Zone Alarm!!!!!!![sucks by the way], not enough system RAM, just to name a few, any of these a possibility for you?
I have a friend that was trying to play online games and burn DVDs at the same time and couldn't figure out why his burns always failed, I don't understand exactly how he was pulling that off in the first place, most all of the burning software I'm using pretty much takes over the machine until the burn is completed.
And actually the 16X Memorex is better made media than the older burn rates were, probably from the speeds they have to run at being so high, forced them to make a better product.
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