I was actually contacted by them today. To me it sounds like a terrible idea, and one that is open to all kinds of potential problems.
Before striking out on my own as a composer I worked for a software company writing music for a mobile app. The moral of the story is that venture capital guys wanted to take the company in a horrible direction, they ultimately crushed us, and it ended with myself and a few others in a 3 year lawsuit… So the last person I would ever trust to respect my percentage of left over royalties is a “high net worth investor”.
I could definitely be wrong, but to me it sounds VERY predatory.