I have grade A now and they fall apart just as quick as grade C I find. I had grade C last time, both are good. I'd go for the cheaper one just because I'm frugal like that :)
I seen the IAL concentrate in stores. I'm sure it's the same as the leaves but I'm not sure. Probably be cheaper to buy the leaves though, since you can use them a couple times and the extract is gone with the old water.