I suggest you read the relevant 'Results & Discussion' threads for each drive before making a decision.
I haven't used any of these drives, but if CD-R writing quality is important, I would look at the Samsung or Pioneer first. The recent predecessors of these drives looked like decent CD writers.
For DVDÂ±R I would be inclined to look towards a Lite-On. Their recent drives looked like they were still decent DVD writers, but I have some doubts about the F series from what I've seen,
IIRC, the Asus DRW-24D5MT is a rebadged LG and the DRW-24F1MT a rebadged Lite-On (although it appears that it could be either an E or F series).
As Albert mentioned, if writing quality is paramount you may wish to consider a Pioneer Blu-ray writer. They can still be considered 'real' Pioneer drives