I used mine in a recording studio for 9+ years. It sadly died a couple of months ago and I replaced it with a Mac Studio (which has been a phenomenal upgrade as software has caught up). I wish I could have waited for the next mac pro, but sadly timing didn't allow for this.
I think as a design it was quite interesting, but it didn't really fit into any spaces that well. It felt very much form over function/aesthetic. It was quite attractive when no cables were attached to it. But when you're in a studio with all ports in use sans the second ethernet port, it becomes much less visually appealing. Most of my clients were surprised to even know it was the computer, and that became a talking point.
Performance wise, it was a very good machine. Could do a lot, but was quite noisy, and difficult to clean. So was prone to running quite hot. I don't have the same issues with the Mac Studio.