I personally prefer a mixture of US and IEC symbols, even though my teachers at university tend to kill me when I draw the resistors with the zigzag line and inductors with the black box.. I do this mainly because I tend to have bad drawing skills, meaning, a square resistor wouldn`t be a square but more like some sort of smashed, mushy thing which could be identified as either a resistor, an inductor or even a fuse. So I write the zigzag line to tell "that is a resistor" and use the box for inductors - because the loop-inductor can be quite simmilar to a badly drawn zigzag-resistor...
What I really hate is the difference between all those logic gates, I can`t really focus on one way to draw them, switching between styles whenever i feel like doing so...
Regarding the LED-Thing: I prefer L-E-D. I also prefer to say Serial ATA and not Sata(n).