Lately, I've found that the little E1e with a Lumens Factory EO or HO lamp, driven by an RCR123 li-ion makes for a wonderful light indeed... if only single output.
Agree that Surefire should make an LED/reflector to fit in the E1e head that can be powered by up to 4.2v (li-ion is a superb rechargeable power source for this little light). I've stopped buying Surefire lights, in part because most of them can't be powered by li-ions and using/tossing primaries is such a waste... plus, most of the time once you've used a primary a little bit, you're working with w partially worn out cell. With a li-ion, you can start every day charged fresh-up! Surefire's missing a big boat in my view by refusing to make lights that can compete with the wide multi-levels and multi-power sources of Quarks, Nitecores, etc.