Hello Bose:
I too purchased the DART Devocalizer.
But like you it doesn't filter that well. At least the latest version.
Just to give you an idea, I would put "DART Devoc" between Vogone 1 and 2. If you like the DART adjustments you'll like Vogone 2 adjustments even better.
But like any software it can be improved to remove "VOCALS" even further. After you work with Vogone 2 you can post your suggestions in the appropriate forum for the next version of Vogone.
Do read the manual that comes with Vogone 2. You might have better results after reading it. Just don't expect miracles. At least not yet.