There's the transatlantic difference.
A 'simple' emergency call isn't recognised in my world. PAN gets attention, MAYDAY gets instant response. "I am declaring an emergency" will suffer cocktail party syndrome (not significant enough to penetrate the background noise).
I spend my standby time listening to 121.5, 156.8 and 243.0 and reacting (or not).
And the only time in 28 years I have transmitted MAYDAY an engine had stopped in the circuit and I really fancied landing on the cross runway, so telling everyone in forceful terms seemed appropriate.
Sven