I haven't tried the pills but the candies gave me heartburn as well. I was then afraid to try the pills. I've stopped taking all pills for a while, I think they sit in my stomach and the coating (or maybe one of the other fillers) irritates me, so, there may be some that are OK but in general not so good for me. Then again, I do have a motility issue and not as sure about GERD/IBS.
If you are looking for other things to try, I once used Mastic Gum pills, they made me burp a lot, not sure if they did anything else but it did relieve some discomfort. Supposedly they help heal stomach and maybe have an affect on h.pylori but not proven in any in vivo studies that I've read.
So, I said I don't take pills but I do use DGL Licorice, eat 1 or 2 of the discs 20mins before a meal. They mix with the saliva to work better and no coating on them to irritate me. Works for me, ymmv.