As of June 2015, Rust-Oleum NeverWet, Kiwi Camp Dry and Scotchgard Fabric and Upholstery Protector are highly-rated waterproofing sprays. Each averages more than four out of five stars in online user reviews.
Rust-Oleum NeverWet has an average rating of 4.2 stars at Home Depot. Reviewers say that it is easy to spray, protects well and does not have an unpleasant smell. Kiwi Camp Dry averages 4.4 stars at Amazon.com. Positive reviews mention that it dries clear, provides a strong barrier and does not stiffen fabric.
Scotchgard Protector has a mean rating of 4.7 stars at Wal-Mart. User critiques say that it prevents leaks, repels spills and dries quickly.