Will my business/personal internet be secure?

Yes, it will -- MyWiFi doesn't affect your personal or business wireless network.

In fact, it will be more secure, since there will be no more handing out or posting your network's password. Simply password protect your main router with a password, and don't share it with your customers. Then plug your MyWiFi router into your main router, creating a separate network where your customers can log in with their social media credentials -- with your main network protected!

This way, you can continue to use your main network to transmit personal and financial information, while still providing your customers with free WiFi.