All I have is the E1 which I like a lot.
According to Flashlightreviews, the
E1 has about 1.5X the total output of the
ArcAAA when both are on fresh batteries. The E1 beam is more concentrated so the hotspot lux is about 2.5X that of the Arc AAA.
I like the flat runtime curve of the E1, although the Arc goes longer on an alkaline. I read somewhere that the E1 will run flat for 5+ hours on an AAA E2 lithium which, interestingly, is close to the 5:30 the Arc AAA gets on the same lithium. Given the 50% higher output of the E1, it looks like the E1 squeezes more out of a lithium AAA than the Arc, but get's less out of an alkaline AAA, probably due to its' extreme regulation.
Overall, I really like the AR glass window on the E1 vs. having an exposed LED. I also like dealing with 4sevens' FenixStore: first quality support and service every time.