From Wikipedia (read "caveat emptor")
Petroleum ether, also known as benzine, is a group of various volatile, highly flammable, liquid hydrocarbon mixtures used chiefly as nonpolar solvents.
Petroleum ether is obtained from petroleum refineries as the portion of the distillate which is intermediate between the lighter naphtha and the heavier kerosene. It has a specific gravity of between 0.6 and 0.8 depending on its composition.
Benzine should not be confused with benzene. Benzine is a mixture of alkanes, e.g., pentane, hexane, and heptane, whereas benzene is a cyclic, aromatic hydrocarbon, C6H6.
also from Wikipedia (and still "caveat emptor")
"Naphtha is a group of various volatile flammable liquid hydrocarbon mixtures used primarily as feedstocks in refineries for the reforming process and in the petrochemical industry for the production of olefins in steam crackers. It is also used in solvent applications in the chemical industry.
Methinks that fuel-grade naptha (like Coleman fuel and most lighter fluids) is probably the lighter distillate that is tighly controlled for specific gravity and levels of soot-producing oils and contaminants.
I would be a lot hesitant to use solvent naptha from Home Depot or wherever as a fuel for the same reason as I would be hesitant to fill my car with no-name bulk fuel from an unknown source. Sure, the Coleman fuel may be noticeably higher, but with what little I use my lantern the last can of fuel I bought lasted more than two years. It costs me more in time and gas driving around to find a deal on fuel than I can save by burning a substitute.
Brad