I’ve been running dual screen display on a i7-5500 fanless pc for 4 years non-stop. I think stability is more on how you optimize the windows. Most of the fanless pc should works.
There are a number of alternatives on the market now for Compute Sticks but most run an Atom processor over the M series CPUs the Compute Sticks had. If you need a powerful-ish device the ones running Atom processors may not cut it. I have seen ones running Intel Celeron chips such as the J3455 and J4125 which would perform similar to the 5 year old M5s I am using. Be sure to check the PassMark score of the processor before you buy.
For those looking for numbers, here are some common PC Stick CPUs PassMark scores:
Intel Core m5-6Y57 (what I run) - 2332
Intel Atom x5-Z8350 - 914
Intel Celeron N3450 - 1924
Intel Celeron J3455 - 2271
Intel Celeron J4125 - 3092
As far as other specs go, 4GB RAM is a minimum but I encourage 8GB for most systems especially when using video. For storage 64GB is also the minimum when running Windows 10 as the base OS takes 20GB in reality and if you have updates, you could run out of diskspace on a 32GB drive. I prefer the sticks over boxes because they can plug directly into the HDMI port of the display. Often these can be powered by the on-board USB port on newer displays meaning you only need one power cord to make it work. You can use TeamViewer, Chrome Remote Desktop and others to manage the display computer. For my systems, I use Kaseya.