303 Fabric Guard Water Repellent Spray vs Waterproofing Wax for Leather: which is safer?

Where these two actually differ

• We flag Volatile organic compounds (VOCs) and off-gassing, Respiratory exposure during application, Skin and eye contact during handling and Persistence and bioaccumulation potential (if PFAS-based) on the 303 Products and not on the Nikwax.
• We flag Respiratory irritation or fume inhalation during application and PFAS in water repellency treatment on the Nikwax and not on the 303 Products.
• The 303 Products is water repellent spray coating, active chemistry undisclosed where the Nikwax is wax-based waterproofing, which is most of the difference in these two grades.
• The gap is 25 points, wide enough that this is not a close call, and the Nikwax is the one to buy.
• We are less certain about the 303 Products grade, at 35% confidence against 78%, because it discloses less.