When people started using SSDs in their HDRs, I figured I should give it a try myself. I just went to my friendly local Micro Center store and got a PATA-to-SATA adapter for about $10. No recognizable brand name, but it worked. I didn't put it through the sort of lengthy testing that Mackie did when choosing a drive to use in manufacturing, but I never had a glitch with it.
If you'd feel better with a reliable brand name adapter, Startech
https://www.startech.com/en-us/hdd/ide2sat25 makes a couple that wouldn't cause me any need to worry.
The issue that you might run into is similar to that with hard drives - you can't find one small enough to be economical.
I don't know if you can make what appears to the operating system as multiple disk drives out of one SSD as apparently the floppy emulation with flash memory cards can do, but nobody that I know has ever had success in getting the HDR (or d8b for that matter - same OS core) to recognize multiple partitions. When I tried the SSD, I got a 120 GB drive (also really cheap at Micro Center) but those seem to have gone the way of the dodo. Since the OS doesn't know how to address more than 130 GB, unless you can still find small SSDs, you'll be buying lots more memory than you can actually use.
By the way, I didn't find any significant improvement in speed, nor did I really feel the need for it, when using the SSD. It's one less noisemaker, but my recorder is located where its mechanical noise isn't a problem for me. After a bit of fooling around, I swapped out the SSD (and put it in a laptop computer) with a SATA hard drive. At the time, SATA drive sizes were soaring, so I could buy new 120 GB drives for under $20, and, being an analog curmudgeon, somehow feel more confident in a mechanical drive that I can hear odd noises from when it's getting ready to fail than in a dead silent (alive or dead) SSD. Your mileage may, and probably will differ.
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