Are the blind spot monitors really BEHIND the rear wheels? Isn't that behind the spot you already can't see because of the wide rear post? Seems to be ill-conceived and poorly executed location.
The blind-spot monitor in my '17 Pilot is in the passenger side-view mirror, so it give a huge panoramic view of the entire right side of the vehicle. No road grime here and it seems to function quite well. It works so well, I find my self playing with it (it's activated both by the right turn signal and by a button on the end of the turn-signal wand) that it sometimes creates a distraction (as does the lane departure and collision avoidance systems). I end up turning all this crap off so I can focus on driving.
They're in the rear quarters - but they BSM works with the car alongside the car, until it passes the mirror...so it does a good job.
I have the audible warning off, so I just have the lights.
My first Challenger ('09) didn't have this feature - I've always run the side mirrors in "wide" setting so I can see the next lane and don't have blind spots.
With the '16, I like this feature - and it alerts me to cars that might have changed lanes closer to me or slip in...its a great feature to have, especially driving at night.
By far, my favorite features are the backup camera and the Rear Park Assist - it take out the guessing.
PS: the Convenience Group also has the Cross-Path warning that's part of BSM. When backing out of a parking space - its alerts way sooner and if you have pedestrians, cars coming it sounds off. That's a very handy feature.
So in summary - I'd get one that has this feature; it comes in handy. It also gains you HIDs if you don't have another option (SP Appearance Grp - if getting a SP model).
It might seem expensive but HIDs when they were a stand alone option were ~ $700 in the early years. This also adds remote start for the A8 equipped models (price is little higher w/ A8 + DCG option)