My garage floor is level for all practical purposes and whenever I put the trike away I do the same thing .. put it in reverse, turn off the engine, then release the reverse button to normal. When I turn the key on to start it again the first thing it does is release reverse and turn on the neutral light. I never use it as a brake to park on inclines. I use 1st gear always and if it's a fairly steep grade I find another place to park. On my Roadsmith I also have the parking brake that works in addition.I only use reverse as a security measure. At home, my parking space is slightly sloped, so I back in, over a 2” X 4”, let the trike roll against the 2” X 4”, then put it in reverse before shutting down. Nobody is going to move the trike, unless they pick up the back tires. If they want it that bad, they will get it, in reverse or not. When I"m ready for the next drive, I can start up my ride, and let it idle for a few minutes. I never leave the trike in reverse, when under pressure.
Out & about, I use first gear. If quite steep, then the Velcro strap comes out to go around the front brake lever. The strap is permanently on my right handlebar – slides down in the handlebar tunnel and is not even noticeable. On a group ride last year, had to stop on quite a steep section of road (because of an accident) and put it in first to try to hold it stopped, and it turned the engine over, and would not hold. I ended up putting the front tire against the embankment on the shoulder. (This is before I got the Velcro strap.)
Rich, you’re lucky on your parking brake. Even when adjusted properly and pulled on hard, I can push the trike by hand. As far as I’m concerned, it is a worthless accessory.