I own a 20L (5 gal) Wedco water can with spout, and a 10L Wedco gas can (don't tell CARB). Very high quality, though fairly heavy especially when full.
My recommendation would be to skip the spout since holding a 20L can full of fuel and trying to pour the fuel into a fuel tank is an act of gymnastics and weight-lifting all at once. Get the Super Siphon. As a matter of fact, get at least two, one for fuel and one for water.
P.S. I will say the Wedco can that I have is a little taller than a Blitz can for instance, so I'm not sure if you might have clearance issues. You can always test fit my Wedco water can assuming it's the same dimensions.