I've been running my Cetus MK3 with the TinyFab ESP32 CPU (beta) for a couple of months now and can report I am very pleased with its performance. My two main reasons for the upgrade were to use a slicer of my choice and to install a BLTouch, but somewhat to my surprise, my experience is that print quality is besting that of the stock unit
I've put my installation notes online: https://richau.wordpress.com/2021/12/05/cetus-cpu-upgrade-part-1-hardware/
Maybe they will be useful to someone who is undertaking or considering undertaking the same upgrade. I received some assistance from Jack but for the most part I was figuring stuff out myself. My notes cover hardware modifications, issues flashing the firmware, installing a BLTouch and my SuperSlicer settings
The main feature I haven't gotten working yet is WIFI (ironic right?) - in truth I haven't looked into it very far
I'd recommend a modest level of technical expertise if you're going to attempt this upgrade - it's still beta after all. But in my view, the end result has certainly been worth it!
I'd be really interested in hearing from anyone who is also running this CPU: comparing notes, sharing your experience with WIFI, additional hacks or tips, etc. And I'll do my best to answer any questions if I can