I see no reason to get rid of that nec and buy a pioneer, it will do fine. If I am not mistaken Piooneer 109 has a Nec chip in it. So they are pretty much the same thing.
As far as the fluid bearing is conserned, my english is not good enough to explain.
http://www.absoluteastronomy.com/enc...id_bearing.htm has some explenations:
"In addition to their long life, fluid bearings generally have very low friction -- far better than mechanical bearings."
Lower friction = less heat and less noise and longer life. There are of cource some very good hard drives without fluid bearings. The main reason I like it beacuse it is less noisy. All new Maxtor Diamondmax drives has fluid bearings.
The diffrerence between dvd-r and dvd+r is not that big realy, just how they worn internaly and the discs are somewhat diffrent. There used to be burners that only burned one type but those days are over. There also used to be big compability issues when you tried to play the disc somewhere else than in your own burner. Nowdays they are almost the same.
http://www.videohelp.com/dvd has some info about both formats.