Would you mind briefly recapping the other problems you are having with the drive, if any? The two I am sure of are: reading sensitivity and non-recognition of a disc.
I guess I'm a "bit" surprised, because I have resolved my so-called speed issue -- which was my own misunderstanding, corrected thanks to reading some cdrlabs reviews. The drive is only supposed to be able to read DVD-ROM (pressed) at 12x max. DVD+R/RW discs it reads, as tested by Nero DVD Speed and CD-DVD Speed (my testing that is), at 8x max (average 6.25), which both are faster than drives costing considerably more than this one.
Regarding the time it took for writing and verifying (Nero 6 BackItUp) -- about 26 minutes -- that's not bad in light on an average read speed of something approaching 6.25x, it seems. Also the time it takes to verify will vary depending on the software used and the files being checked (compressed or non-compressed, for example I would venture).
On +R discs the Sony DRU510A reads at an average 4.01x and the Teac DV-W50D at 4.68x, according to a cdrlabs
review. There may be other factors to consider as well that might balance that out in the Sony and Teac's favor. But I'm not aware of what those factors might be regarding speed.
I would compare the drive's stated performance on different media: DVD-ROM (dual and single layer), DVD+R/RW, and DVD-Video with other drives, and then, of course, test the DW400A's performance yourself.
If I understand what you're saying, I think I would try another DW400A before I threw in the towel. Otherwise I would go for the Lite-On LDW 401S (
newegg has it for $120). It seems to spec out about the same as the DW400A, but costs more, and being a Lite-On, would probably be worth it. The build quality of the DW400A I don't know, but based on comparing its specs with drives costing a lot more, it seems like a more than decent deal.
Needless to say, if it doesn't work, it's no deal at all.
A question I have is whether that version of NeroExpress supports the drive, although I would imagine it does -- it came with the drive, right (my copy is not handy)?
Let us know what's going on, if you can.