The power LED is fully visible with door closed (not obstructed by door) And the hard drive LED is bright enough so it can be seen flickering through the side vent with door closed, depending upon the angle.
Also with the lights off in the dark, it flickers so bright through the vent that it reminds me of a lightening show.
All in all these lights are plenty bright enough fo me.
seconded. Although I've not got my HDD light plugged in (I think I plugged it in the wrong motherboard connector) and you forget about it fairly quickly. If you want to know if there's HDD activity, just listen for it, as the system *should* be quiet enough for that now, unless you put a loud fan in there.
I've had to put some white tac on the front of my power LED otherwise my whole room is lit up by it and can get quite distracting when gaming (I've got enough lights coming from my keyboard, but that's sort of OK as I can see it in the dark) or trying to sleep.