A reader who wishes to remain anonymous has to make the kind of difficult choice that many of us would welcome. He writes:
I work in a graphic design studio and we have a budget to upgrade our Macs. I can't decide what would be better--a tricked-out 27" iMac or an 8-core Mac Pro. Each would be packed full of RAM and have the best graphics card available. Do you have any opinions one way or the other?
At one time, the conventional wisdom was that you'd buy the latest tower Mac if you were a media pro or serious number cruncher and leave the iMac for "regular" users who simply wanted a capable and reasonably affordable computer. Those days have mostly passed. Today's iMacs are serious hunks of hardware--they're wicked fast and have solid graphics performance. If you're concerned about storage, you can always attach an external drive or two or, in the case of a design shop like yours, move data on and off a server. The iMac also currently enjoys the advantage of having a Thunderbolt port, which the Mac Pro still lacks.
The Mac Pro is certainly no slouch. Ideally you'd wait to see if Apple releases an update to it that adds Thunderbolt and a faster processor, but there's no telling if and when that will happen. And, of course, if you want the greatest flexibility in regard to your computer's graphic performance, the Mac Pro is the better way to go as you can easily swap in a new graphics card.
That said, if I were in your studio my primary concern would be the display. You're in the image business and if your images don't look right to you on an iMac's screen, that isn't the computer you should be using. Sure, you can attach an external monitor to your iMac and use that monitor as your primary display (leaving the iMac's display for palettes), but it seems a waste to purchase a Mac with a display you don't care for.
Given that you're talking about an entire studio full of new Macs, I'd strongly suggest finding someone you know willing to lend you a current iMac for a couple of days. Calibrate the display and have the staff work on the thing for awhile to see if its monitor meets your requirements. If you find the display doesn't suit you--it's too reflective, the text is too tiny because of its resolution, or you find the thing too bright or brash--you may choose to go with the Mac Pro and hang on to your current monitors.
We're fortunate to have a lot of designers who, while waiting for one thing or another to render, stop by to share their knowledge. Keep an eye on this story's comments. You're sure to learn something from those who've been in your enviable position.