My question concerning the specific tube goes beyond it having sealant. If you read the link, the tube itself is re-engineered to actually pinch close whenever there's a flat and along with the sealant, instantly closes the hole so no air escapes. Also the tube isn't round but square shaped, slightly thicker than traditional tubes (some weight penalty there, but I'm a Clydesdale commuter) which helps the tire keep it's shape even if there's less air in it.

I'm planning to join a local group of riders which travel around Greece on daily/weekend excursions to remote areas, and even though I've been exceptionally lucky never to have had a flat so far, would like to take any and all precautions to avoid having to repair one in the middle of nowhere.