St A's doesn't get much swell due to the wierd, tucked away location of both beaches. Also the swells that do come in are, more often than not, torn apart by the baltic onshores. West sands is an almost exclusively long board wave due to the super mellow (read: weak) way the wave breaks. East sands, though more finnicky, is the best bet on a short board. As for the balls out, suicide reef in between the two: I've never heard of it being ridden, probably because you have to thread a line between dry reef. It's possible though, so next time it's big and you find yourself in Fife, drop by east sands and we'll tempt our fates.
West sands is the best, sometimes when you get an offshore wind and a good swell you can get perfectly peeling waves that go on for ages. I've also had a few good days windsurfing on a 4.5 in surf about mast and a half high. (Only happens in winter).
West Sands for beginners and super-long rides on a good swell. East Sands for fast, heavy, brown freight trains on its day (holds up in an onshore too). Long live the St Andrews North Side Longboard Crew 1996-2000!
In the middle of the two sands E&W is an amazing reef break which only works in big 4-6+ swell but is ultra hollow and long as hell, very scary and u have 2 go in mid tide as not 2 hit the cliffs!
coldswell.com