The days of firing up your console and jumping straight into a game are gone. Now, you have to power up, boot to the operating system, and then start navigating around (sounds a lot like your computer, right?). Fortunately, that makes boot time a great point of comparison for wildly disparate storage devices.

Sony equips the PS4 with a fairly slow stock hard drive. Boot times improve by 23% with Kingston's SSD installed, 15% with Seagate's SSHD plugged in, and even 9% when we upgrade to a 1 TB Western Digital Scorpio Blue we had lying around.
Despite the percentages, though, we're only looking at a five-second boost, tops, which isn't a huge number.

Next, we go for a couple of game installs, which is a mandatory process for any disc-based title.
In most cases, storage technology makes absolutely no difference, since you're constrained by the read performance of the Blu-ray drive. If you're hoping start playing sooner with a hard drive upgrade, you'll be disappointed.

Loading a game from the PlayStation 4's UI to the title screen is mildly faster with Kingston's E50 SSD installed, compared to the stock Spinpoint M8 500 GB. The same goes for Seagate's SSHD. But in absolute terms, the experience is imperceptibly similar.
The Western Digital drive, in fact, ends up being a bit slower, though again, not by an amount you'd notice. It's really only worth upgrading for more capacity, in this case.
Despite those tiny performance differences, you're still stuck watching several splash screens before you can get into the game. Let us skip over all of that, Sony, and we'll be happy.

The biggest gains comes from loading an existing game save, which might be what you end up doing most often anyway.
For this test, I used a save point in Assassin’s Creed IV: Black Flag with a few hours of gameplay ahead of it (in Tulum, in case you're interested). Kingston's E50 SSD and Seagate's SSHD perform identically, improving performance compared to the stock Samsung Spinpoint M8 by 33%. I'm not certain that's worth losing capacity in the case of the SSD, but Seagate gives you the bump up in speed and capacity.
Unfortunately, our two-year-old Scorpio Blue turns out to be slower. It turns out that not every upgrade is good for more performance.

Over time, Seagate's solid-state hybrid drive design is supposed to cache hot data (the stuff accessed most frequently) in its 8 GB of MLC flash. In order to better gauge whether the previous chart's performance was truly representative of the SSHD incorporating our save game data into cache, we ran an extended test of this technology.
Loading the same game file 10 times, restarting the PlayStation 4 after each run, we see performance varying significantly. Even the worst run is faster than Sony's stock mechanical drive. However, I wouldn't say it's clear that SSD-like behavior is to thank.

To ensure that Sony's Blu-ray disc check process wasn't adding variance to a benchmark that should have only gotten faster, we purchased a digital copy of Assassin’s Creed IV: Black Flag on the Playstation Network and ran the test 10 more times. The results proved fairly similar.
The first three runs demonstrated quite a bit of difference, favoring the disc-based installation. But the repetitions after turned out to be quite even.
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.