For the last 10 years I have had a foot in both the iMac and PC worlds. Both have their strengths and weaknesses. The company I recently retired from used PCs, so most of my working like has been with PC and various Microsoft OS all the way from DOS to the latest WIN 10. Several years ago during the days of the worst Microsoft OS Vista, Win 7 and their weaknesses to viruses, I switched over to an Apple and an iMac and loved it. It took a lot of reeducation to see things the way the Apple OS worked but I did manage and actually still have the iMac.

However, for whatever reason, I never became completely comfortable with the Apple OS. It seems to do things like structure files and directories the way it seems is best rather than what I wanted to do. And during that time Microsoft has improved to the point that WIN 10, in my opinion is as good as Apple's OS. Apple's hardware is very good but also very expensive. So in my opinion it comes down to a price vs performance measurement. I purchased an Asus gamer's PC with and i7 and 16 GB of Ram. It is VERY fast. LR and Photoshop edits are made nearly instantly. HDR and pano merges can take a few seconds to a minute depending on the number of shots but otherwise there are few performance issues. I was able to put this system along with a 27 inch Samsung high def monitor together for less than $900. I think an equivalent Apple system would have been twice that amount or more.

A pc with a fast i5 processor (i7 would be better) with lots of RAM and suitable harddrive will be far cheaper than an equally equipped iMac. And despite what Apple users may want to think, PCs are used in business and industry to a much larger degree thus ensuring a deep pool of development for new software and hardware. It is much like the phone world - android vs Apple phones. If you like a very structured environment where the hardware and the software are tightly integrated and few changes are allowed - go Apple. If you like a less structured system where you have more control (and a little more chaos) then go to android or the PC.

In short - I see few if any actual performance improvements of one over the other. However, the price and costs differences can be significant.