We have NOW Foods and AOR on the SCIO I always come up wanting the expensive AOR while everyone else wants the NOW foods stuff. I believe it is the absorbability of the product that makes the difference for me, so yes quality matters.
Keep in mind a good percentage of Celiac is Lyme bio-toxins not real Celiac.
see http://www.biotoxin.info/webcasts
3rd video...
The problem is partially corrected with top quality Chlorella to help absorb the toxins from bile before the leaky gut re-absorbs those toxins to re-poison you.
Klinghardt calls for 3-4x12 tabs per day, about the price of a Starbucks coffee per day :)