Just wanted to add a few words about Plextor and their QC since a few poster's mentioned they were leaning towards them for their next purchase.
I personally own the Iomega equivalent of the 121032A which is a 12x10x32x CD-RW drive and it has worked flawlessly ever since it was purchased in 2000. A few friends of mine though, have both purchased and had problems with Plextor drives. One had a 161040A that died right after the one year warranty period expired and he had to pay to have it repaired. The other purchased a PX-708A DVD burner which also died right after the one year warranty period.
The point of this post is that computer hardware can be spotty regardless of the manufacturer. I work for a computer company that makes SCSI and fibre channel controllers and there have been days where I've issued more than one RMA for the same model adapter. I've even talked to customers who bought 2 of the same card and they were both bad.
So far there hasn't been a huge outpouring of complaints regarding these drives so they can't be that bad. We all know it only takes one lemon to sour an experience, but based on all of the positive reviews you hear about these drives, it would probably be worth your time to send the drive in and give it another go round. If you choose another manufacturer's product next time, just keep in mind that there is no guarantee of quality with them either.
The only product I trust to ALWAYS work right are my Technics SL-1200MKII turntables, they are tanks. If you're a fellow DJ you will understand that statement.