I've got 4 SLW's, and a 50# sack of layer feed lasts well over 2 months. They get greens and a couple of handfulls of cracked corn per day, and they free range part of the day (less in winter when it's dark by the time I get home from work.) They aren't laying now, so maybe that's why they haven't been going through it faster. I'll have to seen how much more they go through when they start laying again this spring. We have a Farm and Fleet not too far away that sells the layer mix for about $11 per 50# bag, but if you buy the feed at a pet/feed store it's about $18.
Carol
Carol