I would agree. I'm definitely putting mine on the shifter.
It would still be good to get as many pictures of EOC kill switches that we can. No matter their location. Pictures help to encourage the imagination, and for some people, the dash is the only way they can go. It won't be as big of a pay off in savings (added time coasting with engine drinking fuel).
By having it on the dash, it would take just as long to kill the engine as it would to use the ignition switch. Only difference would be less wear on the ignition, and no cut-out for the MPG gauges. For some, that's enough. Plus there's an added bonus of no risk hitting the switch while shifting. Pick your battles and ammo.
And yes, a momentary switch would seem to be the safest route if it's on the shifter. But on the dash, I'm not sure having a momentary switch would be safer. On a bumpy road, curve, in traffic, etc, having to make sure your finger is holding the switch down the entire time the engine is shutting off, may add more risk? Flip the switch, use that hand for more stability on the steering wheel for another second, then back down to flip the switch again. ???
I hope this kind of a thread will help people compare options and make the best/safest choice for their situation. And to get the link to the "How To" that would help them achieve what they are after.
Edit:
So..... will this thread get to be added to the Wiki - Kill switch page?