Not the same in my opinion.
Datils for me are harder to grow.
Fataliis are different.
A lot different.
Both red and yellow.
Haven't grown either in years.

Check out Devils Tongue too if you are into similar pod shaped Chinense.
None of the above are interchangable for taste.
All are pretty close in heat though.

Id say they are definatly different. Flavors are different and the fatalii seemed a little hotter. Both are good but i love the datil. Also there is a strain called the super datil. I havent tried those but ive heard tha its the same as the fatalii. Let me check i may have some extra datil seeds.

Hey judo, if you wanna grow the datils email me. I have plenty of seeds.