So I've had this vega a while now and due to the evil influence of this forum I discovered DX. I just received the Cree XR-R2 (wg) star's I ordered a bit ago (the ultrafire flashlight came quickly, the bulbs sat in customs for a while). So I took apart the vega, de-soldered the luxeon star and soldered on the cree. I decided to add a steel washer as a spacer as the cree's metal base was ~1mm thinner. I took some cheesy before and after shots in my basement and the after is astoundingly brighter at the ~9ft distance from the shoe I used to hold the light to the ceiling. The problem comes up with how now f the light is bumped, it flips off. Also it appears as if the runtime on the light is around 20 minutes...
The runtime thing I don't think directly correlates to the led as in the couple of times I have used the light this fall it has switched over to the about_to_die low power mode with flashing rear indicator. I think the batteries are on their way out and will see about putting in some NiMH AA batteries I have into the housing. The ones there now are 2000mAh and the rechargeables I have are 2500mHa so that will be a nice bump though I may find a problem as the stock ones appear the be flat-topped. I think there's enough leeway to handle the button tops on the new ones. There is also the possibility that the old batteries weren't fully charged despite the indicator... indicating they were.
So that's where things stand, may have killed my light, may just be the end of the ~3 year old battery life where they were recharged nightly in the dark months all that time. If nothing else I get a much brighter light that will work fine for my current commute on the occasions I bike instead of run in the winter. Unfortunately I will probably be tripling my commute shortly. More to come with the battery swap and checking the connections (slight possibility that I loosened a connection in the led swap and checking out the battery pack), hopefully tomorrow.
One question I have is that on the new LED's (I got two for fun at <$7) the 'bulb' is attached to the led/star with a rubber cement moist type adhesive. On the first I brushed off the excess and got an air bubble under the dome. Is there a preferred optical adhesive to use here? Working in a lab I probably have a few options to try but work saw fit the other day to lay off our Swiss machinist who would know exactly which drawer the proper acrylic was in and how long before it reached it's expiration date.