I don't know the percentages either.
I tried to do my estimating as I would at the table.
The Ace wins with stiff K offside, and breaks even with stiff K onside, compared to the finesse.
When LHO has Kx, we need him to hold 3+ diamonds. When he has Kxx we need him to hold 4+ diamonds. Doing the best I can without looking up suit split percentages, I'd estimate about 12.5% for the stiff K offside, about 15% for Kx and 3+ diamonds (Kx being 25% and 3+ diamonds being somewhat over 50%) and about 2-3% for Kxx and 4+ diamonds. Total of about 30%.
The hook wins 37.5%, since it is a straight 50% proposition but breaks even, rather than wins, 12.5% of the time.
Looks like the hook to me. Having said that, my instinct is exactly the same as Justin's....the A seems best on a gut level. However, at the table I think I would do the finesse. I'll wait to see if the probability whizzes here can show me that my gut is smarter than my head
edit: My error was that I forgot to realize that the A breaks even on many other hands...Kx of spades onside and the diamonds lying right for us. That's what my gut was telling me:)
'one of the great markers of the advance of human kindness is the howls you will hear from the Men of God' Johann Hari
2N=GF raise
3♠=extras+diamond single
4♥=control
Do not have the exact cards, but they were not very relevant.
You are 2nd to bid after a pass from your righty...You are NV, opps are V...2/1
Opps leads are 3rd/5th
If I recall correctly, the lead was the C9 or C8..