Some posters have referred to the extra distraction of reprogramming GPS in flight and selecting new VHF freqs. The latter is compounded by having to click through more digits on 8.33 radios.
In his article '
Visual Navigator', written by Neil Williams 40 years ago, there is the following, which I think still applies today:
Nobody has immunity from collision risk. The golden rule for visual flying is nine seconds with one's head out of the cockpit for every one second in.
I often wonder whether there is too much unnecessary VHF traffic in Class G airspace - another distraction. Not to mention that some pilots relax their lookout when they're talking to somebody on the ground on the basis that 'ATC are looking after me'. It might be an interesting experiment to have a 'radio silence' day in which all pilots in Class G operate with comms switched off - that would sharpen lookout!