Are there geographical differences in customer requirements that would allow you to differentiate your solution based on your local market knowledge?

The existence of the US company reduces your market risk. If you have a handle on technical execution, then technical risk is also low. That leaves sales and scaling. If you can grow quickly in the European market, you could even be acquired by the US company for customers rather than technology. Or vice-versa. VC funding is no guarantee of long-term success or healthy management teams.