The replacement "spill-proof"/"enviro-flo" nozzles for all fuel cans is one of the biggest jokes the government has ever come up with. "Spill-proof"?, who are they kidding. As CurlyDave said, the extra fuel that you spill with these nozzles more than easily makes up for the piddly amount of fumes that may escape from the older cans. People have become so fed up with this idiotic design that most are more likely to just unscrew the nozzle off of the can and use it solely like that, which is even worse than the old cans.
I bought 3 diesel cans within the last year and made sure that they had the nozzles that are similar to the older style cans. This nozzle has the vent tube built into it, but has a regular cap on the end like the old cans. This version of the "EPA" nozzles is tolerable, but none of them will ever empty as fast as the old ones. I'm always on the lookout for older fuel cans and I plan to use the ones I have for as long as possible.