!mprovise, the silver one was the best seller. Black second and rainbow nearly as popular as black even though it was $10 more. The rainbow one was coated with titanium in a PVD method and electro shocked like they do for anodizing. Much like a tie dye T-shirt, no two were the same.
Not much was written down about PK's consumer lights. At least that I have seen. They just did not take off. It was as if the flashlight world skipped right over them as the competitors flaunted bigger numbers just about the time they arrived. So between the shaping and the "paultry 360 lumens" the PR-1 was kind of seen as that crazy uncle Fred's flashlight. The lumen wars at that time had begun to boast huge numbers with quick fade while PK was touting steady output at lower numbers. He coined the phrase Fake Lumens while the market yawned.
PK really did the PR-1 right. It really does seem to run forever on high for a single CR123 light. While it’s been in replaced as my normal pocket carry I keep one in the truck and one on my dresser. I like to think of them as what a general purpose E series Surefire would have been like, only smaller.
I half press mine to medium out of instinct but have never just left it turned on to see how long it'll run or if it fades over time. I use mine a few minutes a week with a 650 mAh nitecore RCR and charge it a couple times a year. When the fuel cell runs low it defaults to medium then quickly to low. When it does that you have about 5 minutes to swap cells or it dims rapidly to about the brightness of an incan maglite solitaire.