As a bicycle light hoarder, one of my biggest annoyances has been with propriety mounts that each company creates for their lights.
I recently have been riding with Magicshine Allty 1000 and 2000 lights, and was very excited to see the Garmin 1/4 turn mounts integrated into the light itself.
A lot of other companies have adapters for GoPro or Garmin style mounts, but always at an additional cost and bulk. With the K-Mount/Bar-Fly and other companies making computer mounts more popular, is the Garmin mount the future?
Resurrecting this thread... I'm a bike light hoarder as well and have tried many different lights including older Fenix AA to custom LED lights (remember the Min-T here on CPF from 10 or so years ago?), NiteRider and now Knog and Exposure Lights.
I have a Garmin 810 with a K-Edge 1/4 outfront mount but I don't have Garmin lights. They appear very secure for cyclo computers and probably will do for lights as well.
I notice most lights now (Knog, Lezyne) use silicone straps to mount which works quite well but I'm always worried it will wear out and your light will disappear without you noticing. My new-ish Knog Cobber uses what appears to be flimsier silicone and my rear light tends to drop down on the seatpost during my rides.
My NiteRider Lumina OLED600 is mounted under my K-Edge with a GoPro mount - vs. the over-handlebar mount which is too tall, ugly and strap is annoying to attach - which is good but It does make the light protrude out front quite a bit. It also means the light is mounted upside down which makes it difficult to access the buttons.
The one mount I do prefer and works extremely well is my Exposure Lights Strada 1200.
https://exposurelights.com/products/bike/road-lights/strada-mk10-rs The mount is easier to use than to discribe: the mount wraps around your handlebar using a piece of rubber and tightened via a hex screw, the mechanism that holds your light is a disc that you lift up and the light fits into a bit of a 3-sided mount. You'll have to find a video to see what I mean. In any case, at first, it seemed a little flimsy but, I've had this for over 2 years and, even though my light is a bit bulky, it is rock-steady and stays in place even over harsh bumps. It also allows for over AND under handlebar mounting which is great since I prefer under handlebar mounts.