Not all have printed characters
I have a similar keyboard to the one reviewed, branded TECKNET. The keys have translucent inserts for the characters - the led lights shine through them.
The leds are the only bugbear on the keyboard. Who in their right mind wants flashing or strobing keyboards? When the key is accidently pressed to select a different lighting style (the ScrLK button), it takes 8 more presses to get back to the 'constantly on' option. Which I invariably overshoot because it has p'd me off and I'm bashing it :-)