Depends on what "performance" you are talking about.
In terms of "versatility features" like multiple modes, tail standing, and battery selection, the E1B is pretty weak. Also, in terms of shear lumens and lumens/watt, there's tons of lights that stomp the E1B. Such as...
Quark AA or 123
Fenix LD10 R4, PD10 R4
JetBeam Jet-I Pro, RRT-0
NiteCore D10/11, EX10
...and pretty much any other single cell AA or CR123 with an XRE or XPG emitter.
E1B has an optic though, so it's beam is very different from the lights above and a direct comparison is therefore difficult. The E1B is also very expensive, but build quality and warranty are supposedly reflected in the price.