Prefered hardware for LCNC

Hello
So I want to set up LCNC for running a Onefinity router but have several options for hardware:
RPi 4, with 4 GB mem
Older Thinkpad W510 laptop running WIN 7
Older stationary tower pc running WIN 7, self build more than 10 years old
Newer small form factor pc running WIN 10, self build 3 years old
Newer Thinkpad P50 running win 10

With all options I was thinking of running Mesa 7i76e or 7c80/81

I would prefer the RPi 4 if it’s now been proven a stable build, 32 or 64 version

What is the current recommendations 
Terje

Besides laptops, all of those have a good chance of running LinuxCNC, so download the official ISO, burn it to a USB stick, boot those PC's from it.
Choose live mode, everything will work as normal but it will not touch the existing stuff on the hard drive.

Thank you
If I understand you correct, this means running LinuxCNC from a usb-stick or an external usb hard drive. Will it be as responsive as running it from an internal hard drive, installed in a regular manner?

Terje

Depends on the speed of USB, USB stick or hard drive, but it is very usable.
USB3 with a USB SSD will be pretty much the same.

Thanks again
I did buy a usb ssd to use with the RPI some time ago on another prosjekt, du you think the RPI4 will work for this, it had been fun then?

No idea, don't have a RPI4, nor do i plan to get one at current prices.