Yes, especially if you install Windows
I already have Windows 10 installed on a custom-built PC (i7-3770K, 16GB RAM & GTX970), which is my gaming PC. It is a very capable editing machine and I do have Sony Movie Studio on it. But, that's a consumer video editing program. I could get Premiere Pro, but, the subscription model is scary. Considering that I don't make money video editing, it would be dumb of me to subscribe to a monthly fee for Adobe's Creative Suite.
But, I am an aspiring filmmaker and I already invested in FCPX and MotionX, which I really like, anyway, as is on my MBP. I am only contemplating a Classic Mac Pro because I recently found out that I can afford a used one. And, if I do get one, a Mid-2010 Mac Pro, even if it's only Quad Core, would be at least 2x faster (more if I upgrade) than my 2010 15" MBP that is only dual-core (with hyperthreading).....
hay h9826790 gives good advice and knows what he's talking about.
when you say video editing it's kind of a how fast do you want it/need it, almost any computer will do :E
the macpro is using a cpu that is old (2010 ish about 6 years), there from the i7 970/980/990 gen.
each gen of intel cpu has about a 10%speedup at the same mhz speed so new cpu's are faster.
the macpro is also using old sata2 connections (unless you use pcie drives), older ram etc..
it is a top-ish end computer from 2010 simply
so yes it can edit and it can do 4K, just slower than if you use a newer cpu/mobo/ram
but at what price?
the problem is that if you buy a macpro you spending more than you need to for the hardware, the 'apple tax thing' if you look on ebay you can get dell or HP workstations for more than half the price with the same CPU/RAM
simply your paying more than you need to for a older/slower computer (also ware and repairs may be a problem) so if the computer is for work then it's a less efficient option. it will work but will be slower than the same priced hackingtosh or windows computer.
but in the same way im using one for 1080p work seems fine for me most the time but i also know unless apple dose a u-turn on the macpro ill be moving to a hackingtosh for my next workstation and if you gave me the option of buying a hack or a 5.1 today id look at the hack.
ps ram needed relay depends on how complex your work is 32GB is a good start and fairly cheep but you will want a video card with 4GB vram if your doing 4K
pps my sisters macbook 13" a few years old with a i3 has faster single core speed than my macpro the main problem with laptops is having to plug in lots of USB drives (but usb3 has helped a lot with that)
So, A used mid-2010 Quad-core Mac Pro is like an upgrade path, for me, for the idea I have in mind, even though, it's an old computer....
But, the only thing... the only thing that I'm hesitant with in pulling the trigger to purchase a used Mac Pro.. is how much of an upgrade is it from my current machine? Will MotionX be significantly improved? I've tried using MotionX on my Windows PC under Yosemite, when I was able to dual boot it as a hackintosh and windows machine. And, MotionX ran very well on it. Unfortunately, I haven't been able to successfully hack my PC again to run El Capitan for some reason. Or, I'm too lazy to do it and troubleshoot it, anymore.
So... how well and how fluid is it during the editing process will a Mac Pro Quad-core be under FCP X and MotionX? Since I don't have first-hand experience with this Mac Po or its architecture... I don't know, if, it's worth investing in. I could care less about export time or whathaveyou. I could go have a cigarette for all I care. But, the editing process, when working in Motion X in real time, sorta speak, is the performance spectrum/data that I am looking for.
So, I guess, an ideal response would be from someone who is currently using a Mid-2010 Quad-core Mac Pro and works on it extensively in projects, either professionally or individually as an artist, using MotionX and FCPX.
Thanks!