In 19 years I have had maybe 5 to 10 minor gas-like stomach aches. I have not had one in many years, and I believe it is because I now pay closer attention to whether it is time for another dose of ascorbic acid or not, i.e. experience helps. Ascorbic acid is a powerful internal cleanser, and one needs to build up to it in stages, primarily via one's Bowel Tolerance [indications]. Also, occasionally I get an overly acidic stomach, but a little sodium bicarbonate always takes care of that instantaneously.
The man who "prescribed" Bowel Tolerance doses of ascorbic acid to more patients than anyone in history (over 25,000), over a thirty-five plus year career as a medical doctor, Dr. Robert Cathcart, MD, wrote this about the mineral ascorbates, "I have found that vitamin C in the ascorbic acid form is the best form to take orally. I have been able to achieve, what I call the ascorbate effect, with only ascorbic acid by mouth. Mineral ascorbates by mouth, while being a fine source of vitamin C, do not seem to carry the same punch, probably more electrons."
Sodium ascorbate, has only one extra [antioxidizing] electron per molecule, whereas ascorbic acid has two [and the acid form is lighter because it does not have a sodium atom attached to it]. If you have any acidity problems with the acid form, Daniel, my advice would be to just swallow enough sodium bicarbonate to take care of the problem. My experience is that as you improve your GI tract health, you will be able to ingest more and more ascorbate in the acid form.
As far as "supposed damage caused by mega-doses of vitamin C," [with the possible exception of those with pre-existing kidney disease], I can assure you it is all just biased nonsense and fear-mongering. As Schopenhauer wrote, "Really significant steps forward for mankind go through three stages. First, they are ridiculed. Second, they are heavily fought by those who have economic interests in the status quo. And finally, when the dam is breaking, everyone says: Well we knew it all along." So we will always have the naysayers around, trying to "protect their turf!" You might be interested in what is stated here: http://www.seanet.com/~alexs/ascorbate/misc/ascorbate-lies.htm.
Health is not free! Ascorbic acid is a powerful internal cleanser. Just increase your intake as your bodily health/condition allows [and improves].
If you have any other questions, comments, and/or concerns, please do not hesitate to ask them.
You are most welcome, Daniel, and you are definitely "barking up the right tree!"