I have an E01, since I made the firmware for it. It’s roughly the same size as an E07, and both are significantly larger than a FW3A. However, the E01 does have particularly good thermal performance. Here’s what I measured while testing its thermal regulation:
I don’t end up using it much though, since the beam is cool white and generally more throwy than I usually want. So I mostly use neutral white lights instead, with wider beams.
If you can’t see it step down, it simply has a smooth regulation algorithm. Most thermally-regulated lights these days adjust in steps too small to see by eye, so they need to be measured by a lux meter to determine whether they have stepped down. The E01 definitely falls into that category. It’s very difficult for a human to see a 50% change in output when it takes more than a minute to happen.
Maukka gave very detailed info about the performance of different optics in the FW3A: TLF/BLF/Lumintop FW3A review (18650, 3x XP-L HI cool white)