I noticed streamlight has upgraded the LED in the Argo HP to a C4. Is this a cree?
yes, it is a cree, NOT that C4 == Cree by any means and i'm not even sure that in Streamlight-ese C4 always means Cree, however it is a Cree in the Argo LED Headlamp 61301 model for '08 powered by 3xAAA - at least in my unit.
i haven't seen a '08 LED upgrade yet for the Argo HP powered by 2xCR123A - it may exist, it's just that i get my Streamlight headlamps from Greg at BrightGuy.com and he isn't listing an upgraded Argo HP (his listing still says a Luxeon - which i have a couple of already; one modified for 1x17670). if you have a link to an upgraded '08 Argo HP, i would greatly appreciate a Post containing the link so that i could check it out.
i do have the 3xAAA powered Argo LED headlamp 61301 model for '08 and looking at the LED, it clearly is a Cree in my particular unit - there's no mistaking the appearance.
on the fresh alkalines that came with the headlamp it really is a very bright headlamp. compared to the Primus PrimeLite Race (another '08 model from a diff. mfr., but boasting a Rebel 100 LED) on HI the new Argo is as bright as the PrimeLite Race is on MED. MED on the Argo is roughly similar (to the unaided eye) to LO on the PrimeLite Race. still, LO on the Argo is really too bright for most task/proximity lighting needs (best to keep a 9V Pak-Lite or a H50-Q5 around for that purpose). i haven't compared it yet to a PT Apex or a '07 or '08 Myo XP.
for a 3xAAA headlamp the '08 Argo 61301 is quite impressive both in terms of brightness and the nice beam pattern it produces. i hope that the mfr. claimed burntimes prove to be accurate.
hope this info helps.