Looking at the hi-res of the Maths front panel, and owning a bananalogue euro VCS, I see the differences between the VCS and ch1&4 of the Maths as follows:
The VCS allows independent curve shaping of each stage (attack and decay) on push-pull knobs for the cv-input amount of each stage. The Maths puts this on it's own single knob for both stages, though the VCS style curve shaping would still be possible by patching the channel output to both stage cv inputs, possibly using the two middle channels as a polarizing mixer to get the correct behavior.
I think I prefer the VCS-style here, but I can see the advantages of having two channels in a single module with polarizers/modifiers, as well.
Buy both.