I like the rain sensor, especially when you overtake a truck that sprais liters (or gallons) of rain. The wipers react very quickly, super! (also the automatic rearwindow wipe when you put your car in reverse is nice)
The smog/pollution sensor is also nice, though it seems to work too well, it comes on very often, I think (or is it me?)
The mist sensor works well if you have a damp coat in your car, demisting is a matter of seconds.
In short, go for the Climate pack!