Really, pretty much all burners on the market now are rather comparable in price ($20-$40), with the exceptions of Plextor (~$100 with an amazing feature set, including PlexTools Professional) and Sony (rebadges of other drives with 100% markup). It depends on what features you need and what media you're using.
If you need a three sheep burner for backing up copy-protected discs, get an Asus 1814BLT. If you're just looking for good burn quality on medium to high grade media, get an LG GSA-H42N. If you want a quality scanner/ripper with tons of optional features to mess around with in order to optimize burn quality on all grades of media, get a LiteOn LH-20A1H.