I used to live on coffee with milk and three sugars and a sandwich a day before diagnose. So I had to turn to sweeteners. I did not like the taste in the beginning, but now I'm used to it. I still drink my coffee very sweet although using only sweeteners.
When people argue about sweeteners, they talk about chemicals. But all around is chemicals, including ourselves. So it is better to look at the effects a substance has on the body. I had a discussion with the dietician of my diabetic team. They assured me that all and any sweeteners sold in Britain have been thoroughly tested and are safe. I'm inclined to believe her, rather than some rumours.
The sweeteners trick only the sensory cells for sweetness, so I think they do not exactly treat the body. The sensors send signals to the brain, but at the same time sensors in digestive system and blood vessels send signals that there is no sugar. So the first signals satisfy the body's award receptors making you feel good, while the second make sure that no insulin is released onto the blood stream.
I have no idea if I'm right but I'm basing my reasoning on what I know of human physiology.