Extreme data variation with MaxBotix Ultrasonic Rangefinder

I read the link, that is why I am using the mode in a lower section that is titled:
Sequentially Read Each MaxSonar
which is followed by (Always Works)

I tried getting 3 readings and only using the maximum value of the 3 and I am still getting greater than 12 inches of variation on that one sensor.

Does anybody have experience trying to use multiple sensors on the same project? My next idea at this point is to re-wire and use the section titled:
Control the MaxSonar Sensors to Range Simultaneously
I chose not to use this one because it explicitly says that this works for most, and not all situations.

Could I just have a bad sensor?

Thanks,
Postholes