I don’t have any LG drives, so I won’t comment on those.
In general, I am not thrilled about the burn quality of LiteOn DVD burners, which I use mostly for Disc Quality Scanning DVD media and for reading/ripping. For some media they can burn as good as the best drives, but in my experience they are not generally among the best.
The Optiarc AD-5200/7200/7201/7203 series has excellent burn quality for good DVD and CD media at reasonable burn speeds, they are also fast readers/rippers and can be used for Disc Quality Scanning (but LiteOns are better for scanning DVD media).
The Pioneer DVR-115/215 series has excellent burn quality for good DVD and CD media at reasonable burn speeds, and are fast readers/rippers. They don’t offer Disc Quality Scanning.
The Pioneer DVR-116/216 series is not as good as the 115/216 series in terms of general burn quality in my experience.
I only burn DVDs faster than 8x and CDs faster than 24/32x for testing purposes, but not for burns I intend to keep, so I don’t keep track of which drives performs best at the highest burning speeds.
I have found few exceptions to the rule that 8x or sometimes 6x burning has the highest likelihood of the best possible burn for 8x/16x rated DVD media, and that 16x/24x has the highest likelihood of the best possible burn for 48x/52x rated CD-R media. So I rarely bother with the higher speeds.
I would suggest combining two different drives, e.g. a Pioneer or Optiarc drive with e.g. a LiteOn drive.