Airburst stickies are one of the worst things to fight as a Pyro. Fact.
Grenade Launcher interval is lower than airblast interval too.
Eh, I'm referring to the more sneaky W+M1 Pyros that have the element of suprise on their side.
As a Demoman like myself, there's nothing more humiliating than being killed by a W+M1 Pyro and being able to do almost nothing about it. Stickies don't activate fast enough, and my grenade clip is usually empty by the time a Pyro starts burning me to death. I try to switch to Caber and melee kill them (resulting in both our deaths) but they usually kill me before I can land a hit.
I can definitely put up a fight against airblasting Pyros, though.
...I go on too much public servers.