One of the AS theories behind being the cause of an insulin spike is that as soon as a sweet taste enters your mouth, receptors start the insulin response. Janet is right, we've debated this ad nauseum on this forum, and others are constantly going back and forth based on studies and hypotheses. In the end, it all comes down to how the individual responds to AS that will determine whether consumption is appropriate for you. You are taking the steps to determine BG response, and you'll likely conclude that you're good with AS. I'm not, and the recent research Janet has cited with disruption of gut microbiome and my negative reaction to aspartame keep me away. Many others who have made great sustained progress do fine with AS.

As for the Stevia-sweetened sodas and drinks now available, I can consume these without any issues, but . . . I find them too sweet. So, if there's one downside to LCHF in eliminating sugar addiction, it's that many no longer want anything sweet to the degree we did before LCHF. Yeah, it's a real problem . . .