Hi Colin,
I started on the SR version from the beginning, as I also have IBS. It took me a full four months to get used to them. I had diarrhea and bad stomach cramps every day, but my symptoms were greatly reduced when I was very strict about taking them with a *full* glass of water, in the middle of my meals. I'd eat half my breakfast, swallow the pill with a full glass of water, then eat the rest. For me, it seemed to help. I also reduced my carbs, which also seemed to help. If I ate an overly-carby meal, my symptoms would be worse. Just a suggestion.

Now I can take them whenever, with a lot of liquid or hardly any and everything is fine.