Warning: a long read. Sorry, but this was building up for days and I just had to write everything on my mind. There has been a lot of talk on the subject of SSD vs Fusion drive on these forums, and having read most of them, I decided to give my thoughts on the matter and perhaps help people that have dilemmas. Now, please note that everything here is my personal opinion and while I do try to base it on facts, it is what it is and nothing more. I am well aware that a lot of people will disagree with my views, but I also think people constantly get bad advice by reading these forums. I write this in order to try and help people make up their own mind. And, honestly, I strongly believe the anti-Fusion crowd here are giving some bad advice. First of all, there is no denying that SSDs are awesome. They are also the future. In fact, a SSD upgrade is the single most dramatic speed upgrade you can get for any computer. They are also silent, durable and produce little heat. However, they also cost more. So, what is the solution to this problem - you guessed it, Apples Fusion Drive. Now, we all know what the Fusion Drive is. It is, basically a smart software/hardware solution that ties up a very fast 128Gb PCIe SSD with a 1/2/3Tb HDD. It works beautifuly, and its better than a pure 256Gb SSD for most people, and Ill tell you why. I used to have an iMac with a 128Gb thunderbolt SSD drive and a 1Tb HDD. It was way way better than just with a HDD. I put my OS and all my apps on the SSD. Today, I have mostly the same apps I had then. As I am an illustrator and I have Photoshop (in fact, I have two versions CC and CC 2014 installed because some plugins dont work with the new one), Adobe Illustrator, Corel Painter trial, Sketchbook Pro, Mischief and Zbrush installed. Other than that I have iWorks apps, the new Microsoft Office preview, as well as tons of small apps. I love apps and bought hundreds of dollars worth of them. Now, you may have much more apps then me, but I think its safe to say that the average user doesnt have more. In fact, many people have way less. I just checked the size of my applications folder - it is 24Gb. Yup, 24Gb! Go and check your app folder. Seriously, go and check, Ill wait. I cant imagine that many of you have much more. I installed all the apps I work with, I installed a lot of apps I dont need. I installed everything I could think of, to be honest. And its 24Gb. But just to make this more fun, lets double that! Lets say I have 50Gb worth of apps! Now, the OSX takes less than 10Gb, so lets round that all up to an even 60Gb for OSX plus all the apps I could ever need. Now, I have about 30Gb worth of PSD files, AI files, jpegs, etc. These are not only my active projects, but also a lot of the older ones. I have my archive on a backup disk, but I really dont need more than 15Gb work space for my illustrations (and the fact I have 30 is because Im too lazy to manage that). That is 90Gb total. That leaves around 30Gb free on my SSD (And remember, for this test I actually doubled my app space. In reality I always had somewhere between 45-50Gb free space on my SSD drive) . I originally planned to get a 256Gb one but decided I dont really need it. You see, for everything else - movies, music, books, comics, etc. - I have the HDD drive. In fact, the HDD speed is quite fine for opening files. I worked with some very large (300-400Mb) PSD files from the HDD and, honestly, opening them didnt take much longer than on a SSD (saving them took a bit longer, but nothing drastic). The truth is - if you have the OS and the apps on your SSD, youre fine. And for me, there was plenty enough space for the work files too! So, as you see, 128Gb is quite enough - there is a reason there are perfectly fine MacBook Pros with 128Gb drives. Sure, there is an exception - there are some people that work with very very large uncompressed video and audio files, they also use RAID SSD drives and lots of RAM, etc. But that is a very specific use case. I honestly doubt most people have such requirements, even if they think they do while shopping for new gear. Now, when the time came to get a new iMac, I decided to get the Retina iMac 5K and I decided to take the Fusion Drive option. As I said, I realised I dont need more than 128Gb of SSD space, so my plan was to get the FD and then manually split it to a SSD and HDD parts and just mirror my situation from the previous iMac. To my surprise - this was completely unnecessary. Apple uses some really clever tricks to manage your files for you. They use write buffers for files under 4Gb, they also move files in 128Kb blocks (they dont actually copy entire files back and forth, they are much more granular). The result is - my apps and os still run as fast as they did on a pure SSD, but the system also uses that ~50Gb of free space I had on my previous setup to speed EVERYTHING up. In fact, that space was going to waste while I did things manually. But just as OS manages RAM, now it manages your fast drive storage and does it really really well. Now compare that to a 256Gb SSD setup you can get. First of all, yes, it costs the same, but you have to buy (often expensive) external thunderbolt drives. Second, you have more cables sticking out of your iMac and less free ports (not really a problem, but its still a downside). Third - and most important - youre actually wasting space. Youll probably put everything that would benefit from a SSD to the SSD drive and have more than 100Gb of SSD storage free. What do you put there? Movies? Music? Documents? In my case, yes, there is objectively less SSD free space, but it is used much more efficiently, as it is system managed. The music I listen to the most is most likely on the SSD portion of my FD. And my favorite TV show. In reality, I would have never bothered to move these manually to a 256Gb SSD (no one would). In fact, Im betting that in practical terms, Im using my SSD portion on a FD more than most people are using their 256Gb SSDs. Not that it even matters, because - as I said - there really is no big difference between opening a movie from a SSD or a HDD, but there you go. Of course, if you can afford a 512Gb or 1Tb SSD, thats a no brainer. Sure they are better. Then everything you have is on a SSD and its great. It also costs a lot more. But the FD offers roughly the same performance as that for a fraction of the price. Now, there are reasons to go full SSD. Some professionals need a high-speed storage solution across the drive. Some people just have enough money so they are willing to pay premium. That is all ok. But when someone comes asking for advice, obviously they are asking because they want to get the most out of their money (otherwise theyd just buy the most expensive option without asking). And I read time and time again how people say they should go for a pure SSD, even if it means going just 256Gb. So, there you go. With all this in mind, I recommend to everyone who doesnt already plan on getting some good external space (there are some valid reasons to have external drives) to go for a Fusion Drive. It's great. I don't have experience with the previous generations of it, but the latest PCIe one works really well. Also, please ignore all those remarks about noise, heat and reliability. Im surprised that a lot of people here would rather invest in a pure SSD than AppleCare, for example. Look, we had HDDs for decades. And here people are acting like they are about to fail any minute. Noise? I dont hear my FD. Ever. I tried, ear to the computer and all. And finally - heat - its a couple of degrees warmer. To end this really long post - here is my take on the 256Gb SSD vs Fusion Drive. For most people, Fusion Drive is the better option. There is a reason Apple made that, and not the 256Gb drive a default option, although they cost roughly the same. If you disagree, do me the courtesy of explaining why, instead of just saying something like "You're wrong. FD will break and you will loose your files. SSD is the future, and FD is just marketing. Go SSD, you won't be sorry." Hope this helps and enjoy your purchase, whatever it is.