https://bugs.maemo.org/show_bug.cgi?id=256

Jorma Virkkunen (Nokia)
"The option of choosing the 10 mW transmission power is there only because
certain countries require this in their law. The low power transmission has a
negligible effect on the battery lifetime because the data is sent in short
bursts that last for less than 1% of total time. On the other hand, the lower
transmission power will make it harder to keep connected. Therefore it is best
to use the (default) 100 mW power, unless legislated otherwise in the law of
your country.
"