To me, the Enigma and the newer Mutrons don't have 'it', they sound too clean. The old Mini Q-Tron does though, that's a great filter apart from the volume boost.
The Emma Discombobulator is another one I'm keeping - it's brighter and more subtle then the Fwonk, but that means it works really well going into overdrive/distortion, sounding more like a wah.