We picked out a handful of different devices to test in the PlayStation 4's one drive bay, including Kingston's E50 240 GB SSD, Seagate's SSHD, and a WD Black2 dual-drive. An older WD Scorpio Blue 1 TB from 2011 even made it into our little round-up, if only as a comparison point.
The Kingston SSD lets you switch over to solid-state storage without giving up any capacity compared to Sony's stock hard drive. It adds more than $300 to your already-sizable technology investment, though.
Seagate's SSHD seemed like an interesting compromise, sporting 1 TB of mechanical storage and 8 GB of MLC flash, yet priced right around $100. We didn't know how well its caching algorithms would work with Sony's operating environment though, so we knew we'd have to test it a little differently in order to measure its efficacy.
The Western Digital Black2 is a hybrid technology of sorts, though it differs from Seagate's offering in that its solid-state and conventional storage are uniquely accessible. So, you get 120 GB of flash and 1 TB of disk space in a single device. The ideas is that you choose where you want to put your operating system (SSD), applications (SSD), and user data (hard drive). Unfortunately, the PlayStation never let us get that far, giving us an error that the OS needed a drive with at least 160 GB. As a result of how Western Digital sets this drive up, it simply won't work with the PS4.
Lastly, we have a 1 TB Western Digital Scorpio Blue. We're not expecting much out of it, but I had it lying around, it doubles the PlayStation's stock capacity, and can be found under $100. At the very least, I wanted to know if a larger, non-stock disk helped improve performance or hurt it.
How We Tested
I started with a fresh installation for each set of benchmarks. Rather than messing with a stopwatch to time each run, I set up a video camera to record the process. The video was sent through an editor to trim the beginning and ending; everything between was the benchmark's duration. Each test was run three times and averaged, yielding a final result.

It seems rather shortsighted for Sony to not anticipate users wanting to take advantage of SSD tech. In fact they could have made more $ by offering an upgraded product with an SSD already incorporated (assuming they fixed whataver is causing the negligible difference in performance). Perhaps a few tweaks to the OS through a software update will allow the SSD to make a bigger difference.
It seems that something will need to be done if they hope to have the longevity of the previous generation of consoles.
It isn't. Just seems silly to drop $100 on an HDD upgrade instead of getting PSN, which is necessary for online gaming. But I've enjoyed remote play. It's simple, works, and lets me run a couple races of NFS before going to bed. I'm still waiting for the Vita TV to get updated with US PSN account support so I can play it on my bedroom TV too.
Yea it technically loads faster, but not enough to justify the cost. The gains aren't as massive as on PC. You're also stuck waiting for the developer logo splash screens and the read speed of the Blu-ray drive too, which just nullifies most speed gains anyways.
The Samsung M8 is the stock drive in the PS4. The WD Scorpio Blue was a drive I had sitting in a drawer. We were comparing the difference between HDD vs. SSD. Also, there isn't a Scorpio Black 1TB, they top out at 750GB. SSHDs seem to be the future and newer 5400RPM drives are just as fast as older 7200RPM drives.