@mack505@feistycricket.org here in Washington they treat trikes and sidecars the same. Same license, same safety course, same everything. The difference here is you can test on a sidecar, regular trike or reverse trike. I tested on a standard trike but during the class I rode and practiced with the sidecar and standard trike. I have flown the rig and understand the dynamics for sidecars and want one for my springer. You would be fine on a trike, less worry about the rig and your body position is more natural to 2 wheels. Like a sidecar rig trikes require skills that bikes don’t.