So after a great 2+ years with my TK40.. I'll be sending it back to Fenix tomorrow. over the course of a few weeks I've noticed the light just wasn't as bright as I remembered it.. and this past week the color has really shifted to yellow. I've always used Sanyo Eneloop batteries, and I never really run it more than a few minutes at a time.. It's been warm.. but never hot to the touch.
I finally realized something was really bad when I looked at the LED and noticed it was turning black.. like it was burning.. As of today this is what it looks like:
I also posted a video so you can see the crazy Yellow tint it has now: http://youtu.be/RadqNYiIfaA
Is this a typical failure mode for LED's??
Luckily I called customer service at the US site fenixlighting.com and supposedly they are shipping me a TK41 U2 to replace this TK40. I was very happy to get to talk to a real person, and I'm shipping the TK40 to Arkansas and not China which is nice. I will be very happy with Fenix support if things go as smooth as planned!!
I'll miss the TK40 since it was a great light.. but I'm sure I'll like the TK41 even better!