Klean Heat is nearly odorless, maybe 1/4 (or less) the odor of regular kerosene. Another property, I haven't detected any deterioration of its strength or quality in my 1 1/2 yr old stock (since purchased, don't know when manufactured). I see no residue or precipitation whatsoever at the bottom. Wonder what its shelf life is before it loses a substantial amount of its volatility and other properties -- any petroleum chemists out there want to venture a guess?
Scan Marine vocally admonishes anything but diesel to be used in the Wallas, yet when pressed about Klean Heat, they say they're not really familiar with it -- an honest answer. They're most concerned with its lubrication properties for the pump mechanism, they just don't know. I'll continue to use it until convinced otherwise -- it's just so clean and practically odorless.
My 2c.