Which one is the recommended tool?
Depends on who you ask the recommendation. Given this is a Sloeber thread the recommendation here is Sloeber :-)
But I'm still interested about your thoughts on why using Sloeber.
My thoughts on this subject (not having been able to get "Eclipse C++ IDE for Arduino" to work ever).
The main reason to use Sloeber is that it is supported far better.
Basically I bother to ...
1) write documentation and make video's on how to
2) test boards/setups I don't use. (currently more than 500 boards compile the default ino successfully out of the box)
3) be responsive when there are issues.
4) be even more responsive to people who support me on patreon
https://www.patreon.com/jantjeIMHO this makes the end user experience far better because
1) I limit my response efforts by fixing issues
2) If there are issues there is help available
I'm trying to find out since hours the differences between Sloeber V4 and Eclipse C++ IDE for Arduino 3.0.
Both tools are build on top of CDT and as such have at least 95% the same functionality.
The differences are only at the level of
1) implementation/integration differences of the arduino framework -Sloeber supports multiple versions of the same platform at the same time -
2) specific boards features -like esp debug info-.
3) What is included in the package. Sloeber product comes with everything you need to do hardware/software debug
4) Add on functionality/integrations like the x-y plotter and serial monitor
5) Support for boards which do not come in a json package (like teensy)
This is my opinion. Please share yours :-)
Jantje