I've seen the M3 STYLE mirrors with the red LED in the signal and they kind of show up. If you get closer to it then you can see it. But from a distance I wasn't able to tell if they were on or not. I guess it would also depend on what bulb you put in there as well.
Good luck,
Jason
EDIT
Do they look like these , the ones you are getting that is...or is the light part different?
Good luck,
Jason
EDIT

Do they look like these , the ones you are getting that is...or is the light part different?