Just found this thread,I'm a PPL fixed wing and don't fly much above 2000 feet as I don't need to.
I have had several helicopter flights including a lesson,and did not like going much above 1000 feet.
The reasons for me are that I can see straight down and feel quite vulnerable, as I know there are so many more things to go wrong mechanically than fixed wing.
A commercial fixed wing pilot with helicopter experience ,who feels the same way as me summed it up with these words.
"There ain't no built in redundancy,mate!"
I know it would be pretty catastrophic if a blade came off at 500 feet but it just feels safer at that level.
I'm comforted that some really experienced rotary pilots feel this as well.
The tall building,cliff edge syndrome affect me the same way.
Lister