I don't like high-speed film, and I will use the Natura with slow film in dim areas or for general daylight 24mm photography. Don't dwell on aperture choices with such a camera. After using this camera for a while, you will hopefully have an idea how it chooses aperture settings for certain types/levels of light. I turned off the flash and used ASA200 film in a dark setting with wonderful results handheld. This tells me that the camera chose a very wide aperture or I would have seen handshaking effects. The camera is so small that it actually "gets lost" in a camera bag. This is one of the advantages of such a camera. It is very small and light and has a super sharp lens.
Regards,
Raid