I had an slightly frightening experience as a PPL student/passenger a few years back.
I'd applied to fill a seat on a fly-in to a small unlicensed grass strip in the Midlands. I'd never met the Pilot before although we'd exchanged messages on a forum (not PPRuNe!).
The flight (in a PA28) went well until we reached the area of the grass strip. Despite having a GPS he couldn't find the strip so we spent a good 15-20mins flying around in circles trying to identify it. No problem there - I understand how difficult these things are to spot sometimes.
When we evetually did spot the strip he flew downwind and then lined up on an extended final. On short final (to this short grass strip with hedges at each end) I noticed our approach speed was 85kts! I wasn't sure what to do. Should I - a low hours PPL student and passenger mention the speed or just wait and see what happens. So I waited. And waited some more until I realised he wasn't slowing down. So I rather sheepishly said "are we ok on speed?" to which he looked at the ASI and said "think I'll go around on this one".
It was just as well we did go around. Another aircraft arriving earlier had gone into the hedge at the end of the strip.
Would I fly with him again. Nope! Had I been just a passenger with no flying experience I hate to think what could have happened.