I tend to like LiteOn drives in general for optical, but I don't have anything bad to say about anyone. There has been a lot of consolidation in the market, and many companies selling just a few drive designs.
I can't offer any personal opinion about the Asus bluray drives, as I haven't used them. A number of the can be crossflashed from Liteon firmware for faster rips and the like, so I would expect that Liteon makes at least some of the Asus drives.