I think I understand what you meant now.
But, as far as I am concerned, none of the aforementioned transports reads and “transports” the 1’s and 0’s “on the fly” as you originally stated. Rather, its a matter of degree as to how much they deviate from “on the fly”. 
They all collect and buffer the data before turning it loose.
I think we are having a “semantical” difference of opinion/misunderstanding, in that I think of on the fly as not having a buffer. Whereas, you are apparently speaking to the speed at which the disc is spun up and read and how much data is placed into memory before being released as an output.
According to PS Audio:
“DMP’s advanced Digital Lens technology solves timing, noise and isolation problems through a unique combination of buffer memory and FPGA based digital processing.”
IMO, the differences are with regard to the size of the buffer. The DMP and the new PST are indeed “memory players” (using PSA term of art). I just didn’t want folks to think otherwise based on your original “on the fly like every other spinner out there” comment.
In any event, have a great day!
Cheers.
Just confusion I believe. The easiest way to explain the difference is the PWT rips the data into the buffer just the way a computer does the speed of the disk is controlled by the buffer fill. A regular CD/SACD player controls the speed of the disk to keep the data coming off at the rate necessary for proper reproduction of the sound. The Data in the DMP and the PST is recovered in exactly this way thus (on the fly) the digital lens is a buffer and does not regulate the rate of the data coming off the disk. This would be true if anyone were to use an external digital lens like the Genesis one. I think using the term memory player for something with a 2 second buffer a real stretch. hit the eject on the DMP or the PST the music immediately stops. Do the same on the PWT and it will play on for up to 30 seconds. Have a Great day and listen to the music!
Your experience with the Plextor 8921SAF is very interesting. A couple years ago I bought one of these drives plus an external enclosure to rip my CD library (4000+ discs) and I’m just about finished. This drive has ripped thousands of discs without a hiccup. Even though I already bought the ASUS drive I think I will get the Plextor because I know it is so reliable. If I’m going to go through the hassle of replacing the drive I want to make sure I’m using the best one I can. I’ve had several Plextor drives over the years (I build my own computers) and I have been happy with all of them.
If your experience turns out to be similar to mine, then I think you will find that it performs better than the ASUS. All the best to you.
Wayne.