i don't co-wash with them but because aubrey's is so thick i dilute them with filtered water....2 bottles lasts me 4-5 months as a weekly washer. i think with vitacost after $40 its free shipping so i get other stuff from them like non-perishable grocery items, body wash, lip balm, deoderant, etc. if you use mr. rebates or ebates.com you get cashback.