Can anyone explain....
#2
I don't know which kind of car you have... but it literally is plug-in-and-drive. All that's really left to do is fine tuning. The beauty is, for whatever reason you may need to. You can just go back to the stock ECU in 15 minutes, if that.
#3
It is good if you are cruising/racing through mountains with rapid elevation changes and you have no time (or don't want to) shut off your car to reset the reading.
Is it worth the money in the MSPNP, imho yes.
I need to find a cheap source for a second sensor for myself, but have bigger things to do with the megasquirt before that.
Edit: I guess I need to type faster, always someone else posts above me as I am typing my post