~4 weeks ago I reposted a submission about Aspartame: Aspartame aggravates atherosclerosis through insulin-triggered inflammation (sciencedirect.com) - https://news.ycombinator.com/item?id=43313574
My comment tried to put saccharin, aspartame, acesulfame potassium and sucralose into context. Aspartame is not heat stable, so it's often combined with acesulfame-K. The diet soda industry standardized on aspartame in the 1980's because saccharin has a metallic aftertaste. https://news.ycombinator.com/item?id=43313575
I think saccharin is probably the safest of all the artificial sweeteners. Stevia and monk fruit extracts (herbal sweeteners) are probably okay too, as long as you're not allergic to them.
If you want to try saccharin-sweetened beverages, I've noticed that zero sugar tonic waters at my local grocery store (brand name and generic) use saccharin.