New 27-inch iMac with Retina 5K display
 

I am getting ready to replace my 27” iMac (late 2009) with 12 GB of Ram and 1 TB SATA Hard drive with the new 27-inch iMac with Retina 5K display. I also have a 2 TB Airport Time Machine. My problem is I don’t know: which processor to get; how much RAM; how much and what kind of storage (regular HD, or 1 or 2 TB Fusion drive or 256 or 512 of Flash). I do a fair amount of photo editing with Aperture, which is the main reason I want the 5 K Retina iMac. I am not shooting RAW now, but probably will in the future. Other than that I use my MAC for surfing the web, nothing that requires a lot of power. I really would appreciate any input, especially on the Fusion/Flash storage issue. I will probably get extra RAM from OWC. I will most likely sell my old iMac if anyone is interested.

I have this system and use it on a daily basis for my computer repair business. I would go with the i7 personally for the processor and atleast 8GB of RAM. Since you're spending the money I wouldn't skimp on the processor or hard drive storage. I also have the 3TB Fusion drive, it is certainly faster than the standard. The fusion drive is a ssd mixed with a normal drive. With the programs you use frequently being stored on the solid state so they run faster.

If Money is no issue, then Max out the Ram, get the 2 TB Fusion HD, keep your 2 TB Airport Time machine.

Private me if you have more questions , i have had Macs since 1988