PaulDavis it would probably show if the phones storage was forensically inspected. Thats normally the problem with these features, they seem safe and they are to a point - but its threat model dependant. I would only rely on them if trying to hide stuff from casual inspection.
I suspect at the moment the only real safe space that can be relied upon is a second profile. This probably leaves traces but the keys can be destroyed so most likely the only real option.
All depends what and from whom one is evading.
Obviously profiles are not really the same thing though.