Adam
I first played Brora in 1981 and have played it at least once most of the 25 years since. I do not think that the bunkers have changed one iota, either in size or shape, except that they are probably a little bit more buffed (more frequent revetting, tidier mowing of the edges, etc.). As you can see from Philip's pictures they are very much gathering bunkers a la Muirfield, Dornoch and most Scottish links courses. No hairy eyebrows or lacy capes and bays. A great example is the one at the green of the 3rd. It's a 447 yard hole usually played into the prevailing wind, and getting a long iron or wood to hold its line and not go into the deep bunker right of the green takes a very skillful shot.
Rich