I have not played enough courses to compare and contrast the best, but I am surprised none of the Par 3s at Swinley Forest have been mentioned.
I also thought number 17 at Waterville was outstanding as was Number 13 at The Island Club. Number 8 at Kilspindie and Number 3 at Elie both awfully good too.
Someone mentioned 16 at Golspie, but I think 17 may be better.
Finally, although controversial, I am surprised 2 at RD has not been mentioned.
Ira