Here are my results using the speed control with the LG WH16NS60.

[Chris Kelly]

When entering the 0=99 maximum speed string, my "2012" Blu-ray ripped without error. When ripping my "2001: A Space Odyssey" 4K UHD Blu-ray, 9 files failed. I'm talking the most stable desktop drive I've ever used so far. So for best ripping results, leave it blank. Don't enter any string. For playback in VLC using MakeMKV as a decrypter, enter the string 0=1 to minimize drive speed and noise during playback. Since I hope to be playing directly from my discs instead of ripping to my SSD, I plan on using my LG BU40N for portable use and my LG WH16NS60 for home use since it's quieter, entering the 0=1 string for both drives to minimize drive speed and noise during playback.

[Billycar11]

The Lowest speed on these drives is 2x so I would increase that.
I have also observed speed control on the BU40N to make the drive act weird on the small files of discs I would not recommend using it unless you have found it's fixed I have not tested it for a few months

[Chris Kelly]

Thanks for the warning so I'll know what to expect. If I experience any problems such as choppy playback or no playback at all, I'll first try the 0=8 string Mike recommended. And if that still doesn't work, I just won't enter any strings at all for the BU40N.

The Lowest speed on these drives is 2x so I would increase that.
I have also observed speed control on the BU40N to make the drive act weird on the small files of discs I would not recommend using it unless you have found it's fixed I have not tested it for a few months

[Chris Kelly]

When choosing a slower speed for UHD Blu-ray playback on the LG WH16NS60, I got the same problem as with the LG BU40N. So for the best stability with even these two awesome drives, just stick with the default speeds and don't enter any speed strings.