I was a bit surprised to see Royal County Down's 18th in there. 18 bunkers does not make for a great par five. I'd rank the 1st above it... that narrow channel into a low green adds a very different dimension when you go for it in two.
Narin & Portnoo has indeed changed and both the 10th and 15th are no more. The 10th uses the same chute between the dunes but then doglegs late and rises up to the right. It is still a great hole. The 15th has become a par four.
Once you reach the dogleg on Ballybunion Cashen's 15th it is, for me, one of the most spectacular views of a golf hole.
Shame not to see Waterville's 'Tranquility' (11th) anywhere. It's an interesting hole.
I agree with Ally on Donegal's 8th, which is a standout hole, while the
5th at Strandhill is unlike anything else I've played anywhere.
+1 for Cruden Bay's 6th