I'm in the market for 1TB laptop drive and looking for advice between the two above models. The only difference I see is that the AV-25 - WD10JUCT drive has double the cache memory at 16MB but is intended for video streaming. The intended use is laptop general data storage, primarily photo storage at 20MB per photo. My Dell Precision M6500 laptop uses a SSD drive for boot and working data file storage. I don't find any test data for the WD10JUCT drive, so guessing that it's a new model.
If they are from the same generation, and if they have the same number of platters and heads, then their sustained data transfer rates should be identical. On the cache question, the prevailing opinion in this forum appears to be that cache size has very little observable effect on performance.
The big plus with AV drives is that they will not dwell too long on a difficult sector. The result is that a video stream will not pause and stutter during a protracted read retry, but will instead drop the frame. Of course this requires that the application software is able to take advantage of the ATA Streaming command set.
I read it. I read that your take is that the AV drives default to the behavior of desktop drives without specific video-related commands which my applications will never use. That's consistent with the reply that discussion group Ed Light received from WD. I sent a similar query to WD and am awaiting reply.
I was interested in the cache advantage but you say that cache size has little observable effect on performance, so for my use there may be some compatibility risk and little gain.
FWIW, my photo use is predominately Lightroom, which means that I'll copy RAW photos to a destination and then Lightroom will create a working preview stored on another drive. The difference may be when I use other programs that write to disk for a save, such a Photoshop or occasional solidworks CAD. Put that way, I'm guessing that I won't see much performance based upon the qualities of this drive. My laptop's drive for most work is a SSD.
FWIW, a telephone tech at WD said he tried installing a AV-25 into his personal laptop and didn't get Windows OS to install. Also said that the Scorpio Blue is better designed against small shock. A higher level tech said that the blue would offer much better PC performance.