We finally found a "best" question to which "Pine Valley" isn't the answer!
I'm going with a shortlist of:
Royal Melbourne (West) -- three fantastic, demanding holes, calling for a variety of shots off tees and into greens.
Royal Cinque Ports -- short, tempting and great greens x2, then a long, strong, strategic four.
Golspie -- for lovers of quirk and a hint of golf porn.
St Enodoc -- great linksland, demanding but not overpowering.
National Golf Links -- great mix of temptation and looming disaster, especially at 17 and 18.