you r right, this 四防機mainly for wet sports, or sand/dust/dirty environment.
under the sun, quality ok
no good in the dark.
i use it for underwater photo. Snorkel or Snuba
dry environment, i will use my Lumix FZ100 and Nikon D7000.
Lumix is very handy, good when site seeing.
Nikon is too heavy with extra lens and flash. i use it when need 'quality'