Interesting read indeed, I've been with Esenthel for a very long time, all the way back I bought what were called the 'Company license', before that I had indie license.
For me, Esenthel's stability has been one of the most amazing aspects, second is code clarity|quality even if parts were completely void of documentation back then, quick tampering allowed me to easily verify if it was indeed what I thought it was.
by Stability I mean, I've gone through alot of hardware during my time using Esenthel list is not necessarily in order.
pentium 4 and Sempron 3200+, E6600,Q6600, phenom X4 955,FX8320, 1700X, 5900X and a few other of intels Bridges and lakes.
I've gone through X1800XTX, 8800GTS, HD3870,HD4870,HD5870, GTX480, HD6870, HD7870, 290X,GTX780,GTX970,GTX1070, RX470, and now 6800XT and 2070 Super.
I can name engine related problems to this range of hardware to 5 times(I remember Tottels Benchmarking program, which I used to test HD3870,4870,5870,GTX480 one after another on the same CPU). and I am typically a driver update freak, is there any driver update, it gets installed and 3 of those times were exclusively due to specific drivers mucking things up, and Esenthel wasn't the only program that refused to run with these drivers properly at those times.
Esenthel has been my only goto Engine when I just need to play around with something without having to worry about random crashing, lockups, unable to load projects or need to test my latest play thing repeatedly and very quickly. not to mention, install/download time whenever I've setup a new system or an update etc.
For me programming is exclusively a hobby, of course, jumping from one engine to another frequently but before finding Esenthel, I still couldn't program at all, however, certain things started to click(from the ones who are still around and remember some of my oldest work, might've seen quite huge floppy spaghetti code). I've had a blast playing around with implementing/utilizing Recast and Detour, Raknet, Terrain Generators, Lua scripting, Squirrel scripting,Sqllite, Angelscript and many more things.
Heck, I am going to be honest, I hated the Code Editor(probably someone who were in the devgroups that can remember me making comments about that), after a long while it grew on me when it came to quick prototyping or short code testing, I still like to go back to Visual Studio(includes pruning and cleaning away all the automatic variable from Code editor to VS "export").
but Greg...Now I can't get the image of you getting "Smile-Slapped" out of my head..
Edit: Oh, and I also wanted to say, I still support Esenthel through Github sponsor thingy even though my status on the forum is not listed as such.