There is also the "green factor."

Tin-lead solder formulas are very well known and very reliable.

For green reasons the lead is being removed from the solder formula used in consumer products.
This has resulted in a drop in the reliability of solder connections and the opportunity for consumers to experience failures due to 'tin whisker' growth which causes spontaneous short circuits.

Lead-free solder is prohibited from use on spacecraft and critical military equipment because of this unreliability factor. But you the consumer can tolerate these failures.

(I had a Rino nearly melt down in its very early usage. Probably due to a stray solder ball from manufacturing shorting the battery. Was under warranty so was replaced.)

I'm going on an expedition this weekend and taking a backup GPS because being unable to record points and tracks would seriously hamper the goals of the project.