I have the same drive, but my firmware is GL04, and I have done a speed test and have 2 images below, the first you will see is from a normal CD audio disc, the second is from a Datawrite Dual Layer disc with 7.84 worth of data. I did try doing a dual layer film, but it stopped after about 5 minutes with a message about something it couldn't read due to it being entangled or something, strange thing is I thought that came up because the DVD was copy protected, but it doesn't say so on the cover, surely a DL DVD movie would let a drive read it especially NERO for a test, no?
I may try the same movie on my Samsung writer to see if that same error appears, if it doesn't then it's the Liteon drive!
Anyway here are the images, and I would like to point out that my speed test of the DL disc is similar to yours.
What are your thoughts on my speed tests, as I only inserted this drive yesterday. I wonder why this drive isn't on the Liteon website?
This one below is the DL disc speed test.