I've got a 7000NEX.  I've got ASL enabled, but I don't seem to be getting any action out of it.  I've tried multiple settings including high and never notice it.  In some other cars, I've noticed the difference.  I didn't do the install.  I suspect there is no speed reference wire.  Since the unit has a GPS and is more than happy to notify me any time I'm speeding (bumped it up to 20%, but may just disable it altogether), you would think that the GPS would be good enough for the ASL.

Am I correct in thinking that the ASL will not take its reference from the GPS speed?  It has to be from the speed reference wire?

asl does work off the speed pulse wire, somewhere in the setting menu there is a icon that will show you the speed pulse reading i just cant remember where at the moment.