I'm considering 230V (Europe).
You have a point: Watt is not Volt x Ampere.
But if the datasheet gives me a consumption of 300 Watt, I would assume 300/0.8 = 375 VA which is not a big difference.
This is a real example of a device we are going to install:
The datasheets gives me this info:
"Input voltage: 100 to 240VAC,
47 to 63 HZ, 3A
Output Power: 250W."
3Ax240VAC= 720 VA whichis much higher than the 250 W
