I just got the Pelican Xenon - not the LED version. I think that is the light you're asking about? It is a frikkin awesome light. I am not fond of the twist for constant on lights like SF. Im not sure whether Pentagon is that way or not. I went with the Pelican and I am very glad that I did so.
This light is small, ruggedly build and bright as all get out. haven't run completely through a set of batteries yet, so I can't say anything on that end of performance yet. It is definately brigter than my friend's SF 6P. The clicky switch is nearly silent - which is a nice touch. I am waiting for a tape switch for mine to see if I want to mount it on my carbine - not sure about that one yet.
The other cool thing is that the light comes with a holster. It is actually a pretty decent holster that includes battery storage. Speaking of batts, it came with Energizer E2 - not some no-name batts.
Overall. I am eventually going to get a Pentagon to compare, but right now, I think the Pelican is the best out there for the money.
YMMV
Don
ETA: I forgot to add some features: It has a lockout tailcap, and you can back off the tail cap so that the clickie doesn't work all the way and that it is just a momentary switch. Basically, the tailcap can be twisted to whatever mode you want it to be. A very useful feature if you want my opinion.
Also, the beam is well focused, with no weak spots. Im pretty sure that it is not a shock isolated bezel, and I have no idea whether the SF shock bezels would fit, I doubt it.
D