I was told that it's very common to be latose intolerant. I tried both soy milk and lactaid. I like the lactaid better. It mixed better when making cooked oatmeal. I use milk instead of water. Soy milk doesn't seem to mix well.
Anyway I tried the lactose free diaet for a week then tried some dairy and had abosultly no problems...so now I'm back to my regular fat free milk. No need to switch if you're not lactose intolerant!