Yeah, I must admit. The 1 original mega atty I have from 2 months ago tastes burned no matter what I soak it in or blow through it. And my friend who asked to borrow my used 401 stuff let me take a drag recently, and it tasted wayy better than my 510 mega atty even after the 2 months since I used it.
The 401 does still hit as good as they first did 3 months ago, unlike the now tounge cutting hot taste of my worn down 510. There just so big in juice capacity, I really need that refiling convenience. But yeah, its no marathoner.