There’s always going to be positives and negatives to any drive you’re using…
For example my PC employs an NEC 3550a and a Liteon SHW-160P6S. I didn’t realize it at first, but the combination of these two drives is priceless.
For example the NEC drive simply sucks for doing CD-quality scans in Nero. The Lite-On drive does a fantastic job, and where the NEC flags 200+ PIF errors, the Liteon may only record 4 errors max on the same disc.
I’ve recently come across some media (Philips 16x DVD-R and DVD+R both by CMC Magnetics) that the NEC burns horribly. Yes, they are readable but a quality scan reveals a very poor burn. The Liteon creates a much cleaner copy with this media (when tested with Nero).
For the most part my NEC drive has been a terrific burner (even when tested with the Liteon drive). But unless you use the same trusted, quality media verified for that drive, you will almost certainly find better results with another drive, when using certain types of media. The only example so far I’ve found was the recent 16X CMC media I’ve aquired, burns much better in the Liteon burner, otherwise it’s been comparable.
Another example is the NEC drive creates MUCH better backups when using dual-layer media. The Liteon creates acceptable copies, but the NEC fares better in the quality scan in almost every circumstance with DL media.
There are so many combinations that it’s hard to find a bad DVD-burner, some will burn good with certain media, bad with others.
So if you’re creating backups that you can’t lose and are using different types of media, I definately recommend the use of two burners. Because one will burn better than the other and vice versa, depending on the media type. And media isn’t cheap, I hate to be stuck with 100 discs that aren’t good for my burner— it’s always good to have a 2nd alternative!