I have done C41 a couple of times, but it is not for me. I used the low temperature process at 24C. Still found it too cumbersome to maintain the correct temperature throughout the process.
Not done any C41 since before the pandemic and am currently too skint to do any, but in the before times I bought a 'Sous Vide' cooker, which I clamp onto the side of a plastic bucket, put the bottles of chemistry in, add water until it's up to the neck of the bottles, switch on the heater and set the temperature a few degrees hotter than the chemistry requires.
it'll bleep when it gets up to temperature, and by that time the chemistry in the bottles will be at the right temperature.
I found that worked really well when I was using the Tetenal kit. It was also cheaper than similar devices sold expressly for photographic purposes!
(Though I really don't fancy doing any sous vide cooking with it - I mean, I know the food has to be sealed in a bag, but I'd still worry about contamination!)