According to the TSFL FAQ's.....
"What can I put in my coffee?
If you wish, you may use low fat or skim milk or small amounts of half and half in your coffee or tea. You may also use artificial sweeteners such as Equal® if desired."
I would also say other sweeteners like Splenda are okay. I use them regularly in my oatmeals, shakes, coffee, and hot cocoa. Not sure I could do some of the products without my DaVinci and Torani SF syrups.
As Unca responded, 2 T per cup of coffee. We are allowed up to 3 caffeinated drinks a day, and that is servings, so watch the serving sizes.
Hope this helps.