My logic
Better to have one and not need it than the other way around.
All the vehicles I've worked on, I show their pilots in Shuttle-type Clarke suits. These not only hold pressure in emergencies (they're not real space suits), but incorporate a complete set of survival equipment in case of a landing away from civilization.
It's a judgment call. Rutan's spacecraft were flown in shirtsleeves, and if I recall right (correct me if I'm wrong), so was the Shuttle for a short time.