Tom,
Re Troon Darley, its the second out of the three muni's at Troon. Second that is in terms of length but IMHO the most fun course in Troon incl. the Old Course and Portland. Like all the Troon courses, originally laid out by Willie Fernie I believe. Its basically an inland links playing over some really interesting up and down terrain with some forced carries, blind shots, a burn, gorse, heather and generally small greens. Perhaps not the same test as Lochgreen which is more a "championship" test but still challenging in a more fun way for the average golfer.
The course is surrounded by housing, two schools and a railway, and has no sea views so there's absolutely no chance you'll get any tourists playing it but its very popular with the locals, and a lot of Glasgow golfers which tells you all you need to know. I haven't played it for a number of years when they had an issue with rubbish and dog walkers on the course but if they have that sorted out then I suggest its a hidden gem for those who want to find it.
Niall