Has anyone bought a pre-built from PC Specialist?

Am after a few machines for work. Engineering use, so looking at the 3900X and 32GB of ram.

Sadly the big names like Dell and HP don't seem to do anything AMD above the 3400G so they are all out.
Scan's prices were laughable, I had to choose a "configure it yourself" and every single component seemed to be priced about £40 above market rate with an iffy selection to start with which adds up pretty fast.

Stumbled across PC Specialist who do a CAD system which with a few component swaps (cheaper video RX570 card that can do 3 monitors, more ram, more CPU, ditch the spinning rust for NVMe storage) is about what I am looking for.

The company is a complete unknown to me though

I've handled a few of their machines in the last few years and, overall, they're decent.

I've never used them, but have heard of them. I'm pretty sure HEXUS has reviewed a few of their builds in the past.