From what I've read in the past here from other members who have suited up w/o trooping was that if you go in a mall or a Walmart, you will definitely be told to remove your helmet. Also, don't take your blaster as that just scares people even though you know that it isn't a functional gun, it worries the public.
Besides regular troops and Halloween, the only time I've suited up in the past w/o an official troop was for an outdoor photo shoot in my costumes (TK and TB). You MUST have someone there with you as an added safety. I'd never go out into public suited up all alone. Even if no one did anything to you, you could trip and fall w/o someone there to point out hazards as you walk.