I'd guess on a "Kano K1633" being a possible Liteon 1633S rebadge as well - if not that, probably worse, say a BTC that makes an even worse job of the Mediatek DVD chipset than Liteon - I'm definitely beginning to side with those who say that there is no really good Mediatek chipset drive.
Like media, drive brands are often just a name on the box, and what's in them is made by someone else.
The "stock" Liteon is usually recognizable, some tips:
1. The vertical bow on the tray front is pinched at each end
2. There may be a small "scoop" under the tray centre
- Sony Retail models are about the only ones that change anything on the panel other than colour.
3. Size - current drives tend to be 2cm shorter than most
4. Rounded rectangle button, and rounded rectangle LED
5. Logos printed, not stamped, and on the tray, Left, Right and Centre
Liteon technology names: Smart-Burn for the underrun recovery, Smart-X for adaptive speed control.