It definitely has its sound. I have a slim phatty in a rack with the electron which i use for all my deep bass sounds. A4 gets used from anything sitting in the low mids upwards. i feel you can get a more ‘analog’ moving sound with the A4 because of its routing options.
Slim phatty is also great for getting that simian mobile disco/minilogue/jimmy edgar bleepy appregiator sound. Bit off subject but add a slim to the mix its the perfect combination! I like to blend patches from both synths playing the same thing with eq/filters in ableton, then use the fx on the a4 for the top end of the synth.