No way. Now if I had a sampler of each at the same, which I've never done... but if I did THEN -
I still don't think I could tell the difference.
I'm trying to break myself from Diet drinks... because they aren't good for you. I don't drink many anyway. What I probably won't do is go back to regular soda... non-diet. That because the non-diet drinks are just a LOT more sweet to me.
The best diet soda, to me, is Mountain Dew. Very little aftertaste to me but others think it has as much aftertaste if not more.