I avoid artificial sweeteners because they mess with my satiety signals. They make it harder to just eat as much as I want without tracking or measuring anything. It isn't that I won't ever have any. I don't bring them into the house, though. I only have them when out, because of the self-control issues they tend to cause. But, like ketofire51, I don't really fall under the strict "keto" label. My way of eating is naturally ketogenic (as a side effect), but it's not my main focus.

The vast majority of keto-ers that I know are accepting of artificial sweeteners. Some of them avoid specific ones (like the sugar alcohols) because of glycemic response or gut issues, but most keto people accept them as fine. The goal is to stay under your carb limit and make sure that you are staying in ketosis. If you can do that with artificial sweeteners, and they don't otherwise impact your goals, have at them.

It doesn't knock me out of ketosis but diet soda can be very addictive, which can cause emotional eating and carb relapse. I save it for the movies or when I get an occasional lettuce-wrapped burger.

I don't do soda simply because it is so easy for me to drink my way to calorie overload. I removed it from my diet years ago and slowly let it creep back in over the last 2 years...but now I've kicked it out again in favor of water and tea. I have difficulty meeting water requirements as I'm just not thirsty enough, so soda isn't helpful.