Both are very respectable brands. I would have suggested those two brands that you have mentioned. However, my personal preference would be Lite-On as I've never had any problems with their CDRW or DVD drives. Bought 4 of Lite-On products in total so far and will be more than likely to stick to this brand in the future (unless something bad happens).
Haven't tried Plextor, but seen one in action though. I think it'll be a little difficult to judge which is better out of the two.
If the Plextor is better, I don't think it would be enough to justify the price difference between the two... I can't say I've ever heard any major complaints about either of the two brands, so you should be ok either way.
I know of 2, 411S liteon's, both bought at christmas. Me and a buddy. He has burned hundreds of dvds with no problems. I returned mine after 3 weeks of hassles because it wouldn't burn RW media. I sent him my left over media and it worked fine on his. I now figure mine was just a random dud.
Bottom line is I'm thinking of trying Lite on again next good sale I see.
Ep, glad to see you come back and tidy up...did want to ask a one day favor, I want to enhance my resume , was hoping you could make me administrator for a day, if so, take me right off since I won't be here to do anything, and don't know the slightest about the board, but it would be nice putting "served administrator osnn", if can do, THANKS