My daughter's nutritionist recommended culturelle(a probiotic) for my daughter's digestion. Where is the best/cheapest place to get it? It is more expensive than what i am giving her now which is rhino-acidophilus for children which I get a huge bottle(120 chewables) for$15. online it looks like culturelle is around 20-30 dollars for 30 pills. Seems like a big cost difference. Is it that much better? Any experience with this is appreciated.