Legal regulations for eBikes

Hey everyone!

Just got back from a fantastic ride on my Specialized Turbo Vado SL 5.0 – clocked about 30 miles today on some mixed city paths and bike trails. It got me thinking, with all the different classes and motor sizes out there, how confusing are the eBike legal regulations for you guys? I'm always a bit unsure about where I can legally ride at certain speeds, especially when crossing state lines or even just different county parks. What's been your experience navigating this, and have any of you run into issues with the law or park rangers regarding your Turbo?