Mac Forums

Ok, I want to get a new Mac, and I have a $1600 budget.

I either want a new iMac direct from the Apple Online Store or a used Mac Pro probably from eBay or Amazon. Of course, I can only afford a 21.5" iMac. I already have three monitors, an Apple Wireless Bluetooth keyboard, and Magic Mouse. Which do you think I should get?

I will be doing coding, video editing, web browsing, emailing, Skyping/ messaging, and 3D rendering. I also want the machine to be quiet when idle.
Also, it would be great if you would tell me why. Thanks!