I use orderflow and other quantitative indicators and there is absolutely merit in quantitative trading otherwise you may as well use darts.
If this company's system is a blackbox then the only thing you can go by is verified brokerage statements. The company claims "The AVC algorithm has been used for trading for over 40 years!". So therefore, if they have been using their algorithms they must have regular statements??
My take on this would be that, if they can't provide those statements I would stay the hell away.