Both Asus and Cendyne are selling the Pioneer DVR-105 (normally OEM) in retail-packages under their own labels. I've seen the Asus selling locally for about $50 less than the Pioneer DVR-A05 (retail pack).
OfficeMax and Staples have had the Cendyne unit on sale recently (not sure about current sales) for well under $200 after rebates. (See here for an expired example.)
These drives are state-of-the-art for us consumers. They write DVD-R at 4X and CD-R at 16X (RW discs are at half those speeds).
The Cendyne drives may require a firmware upgrade, but this is a good idea no matter what brand.
