I recommend Fusion Drive or SSD

The iMac I bought due to the high price of the 1TB hard drive. This mistake I would not make. I must say that I switched from a gaming PC with well i5 and SSD. And SSD vs. Hard drive I think speaks for itself. I thought for the office work and so on the hard drive will be enough, unfortunately, is not the case. For my needs the iMac is much too slow to drive. The hard drive slows down the entire system - it has happened to me as 8 years ago, where there has been no multitasking. Once a read access can be almost nothing to start in parallel.

Of course I admit nevertheless 5 stars because it is a good device and it really my decision was indeed the iMac to buy only with a hard disk.

I want to give you only the tip that invest few hundred euros more and take either a merger or a SSD Drive.

My solution: I bought the Thunderbolt adapter Seagate and run my iMac now with a Samsung 840 256GB. The parts cost me 230 and I am therefore driven cheaper than if I had taken the same SSD. The speed is a dream. From 110MB read access to the hard drive to 360MB with the SSD 840. The installation is a breeze thanks to the recovery of Moutain Lion and was completed in one hour.

So my tip. Either buy the same with SSD or Fusion Drive, or hard drive, and if he is too slow you just pimp bit with the Thunderbolt adapter; D ...

The advantage with the adapter - I have the additional 1TB hard drive internally as storage for films etc.