I've built 3 PC's at different levels - a $600 build for my daughter, a $2000 build for my son, and a $3200 build for my work. I'm a freelance VFX artist working with Maya and After Effects etc. and highly recommend building your own. I will never buy a pre-built computer again. It can be an intimidating project to think about doing but it's really actually very easy with the help of a few websites and a couple of youtube videos. I highly recommend it!
The most useful website for figuring out the correct parts is http://www.logicalincrements.com/
This website is constantly updated and breaks builds down to various price points. They make sure that the parts listed all work together.
Another website that can be helpful is https://pcpartpicker.com/ although I've found this not to be as useful as logical increments.
As far as build videos, these guys at Newegg are awesome and break it down in an easy to follow way: https://www.youtube.com/watch?v=VIF43-0mDk4
I'm running an Intel i7-5820 @3.30GHz, 48GB Ram, Nvidia GeForce GTX 980, Windows 7, SSD for C drive (operating system and programs), SSD for main project drive, SSD for After Effects scratch disk, regular platter drives for bulk storage. This is a very powerful setup.
Very cool and beautiful! I'm not convinced that the cost to do it practical or CG was a factor. I'm sure this was a fairly expensive project in terms of planning, shooting, and post-production. The truth is that practical always looks better than CG and if you can achieve something with practical effects (within the budget of course), why would you ever do it in CG?
While it's true that on a 20 day job your edit bays are tied up for 20 days, it's also a guaranteed 20 days. Would you normally be booked for a solid 20 days by smaller jobs?
This is all great information! I've seen many low budget productions add significantly to their post production costs because they did not consult with a VFX Supervisor prior to shooting. Even just paying a VFX Supervisor for an hour or two of their time prior to shooting can eliminate many common mistakes that take large amounts of time, effort, and skill to fix.
In my 22 years of experience of using both, I've seen no difference between Mac and PC reliability.
I'd be wary of using that setup for much if any Resolve work. I had 2012 MacPro tower with 32 gigs of ram and an Nvidia Quadro FX 4800 that totally choked on Resolve, and that was for HD footage.