Between those two drives I would personally go for the Liteon. The LG is a good burner but the Liteon 1693S can be unlocked to allow up to 16x reading and ripping, using OmniPatcher, whereas the LG is 10x and 8x. The Liteon uses CAV, PCAV, CLV, whereas the LG uses ZCLV, CLV below 16x. The Liteon is unofficially supported by the CodeGuys , whereas LG has no unofficially support other than getting a media list from the firmware.
If I was going to the shop, I certainly know which one I would buy. As bichonn says, just check out the two forums