The beauty of optics is that it hasn't changed since Newton wrote the definitive text. However, Last Minute is more accessible, and this is a free version of the highlights in Wilkinson: http://www.medrounds.org/optics-review/index.html
I can't say I did great on OKAPs, but I smoked optics because it's so finite. There's only about 12 possible questions, and they're all iterations on one of them. Put in the effort in and it pays off. It's unlike retina, uveitis, or any other section where you can study the high yield material, then get clobbered by the minutiae.