I got a CustomLED intigrated break light for Christmas. Just got around to installing it this weekend. The reviews on the CustomLED have been pretty good, but I wasn't sure how big a difference it would be compaired to the ClearAlternatives LEDs that I already had. Come to find out, there's a big difference. The vids don't really do either light justice, but you can tell a big difference. Check 'em out.
I put my CustomLED in my wife's 599 (shares same taillight housing as 919 ) and I've ridden behind that bike and I don't notice glare at all. The light IS bright, yes, but it's crisp and directed right where you would see it. I had no issues when glancing at it and then looking away, even when right behind the bike.
Heck, I see more newer cars with OEM LED taillights that are WAY too bright, I think the CLED unit is perfect.
with regards to keeping the stock lens, did you notice anything 'horrible' with keeping the orange signals with the red tint?
CustomLED recommends to change it to the red signal if you're keeping the red lens because "using amber/red setting behind a red tinted lens will perform horribly" according to the install instructions.
I changed mine to red/red.. but I like the look of the amber/red better.