Hi Mauro,
I am by no means a render expert … I am only a 3D doodler, so to speak.
However, I try to do images the possibly easiest way to produce and that they
are for me showable. Maxwell Render allows me to do this because it is for me
easy to use and very logical. I am still using and old version, without GPU support.
The reason why i started to play with Cycles is that i can produce nice images as
well but with much shorter render times. And thanks to Metins tip about the denoiser
i can render now much faster with Cycles (or Maxwell …). That said the learning
curve to use Blender and Cycles is higher for me, because there are much
more settings (node set-up for shaders etc.), but once mastered i should be good
to go.
Eevee is a totally different beast, i was all ears when Chipp released his
course, because i have found no similar course for learning Eevee, which i like
to use later too.
When it comes to direct comparison of render engines there is a nice comparison
available to check out the pros and cons of Cycles and Maxwell.
https://www.blenderguru.com/articles/render-engine-comparison-cycles-vs-giants
Hope this answers a bit your question!
Regards
Stefan