horizon wrote:1. Dazzling other road users (fixed by having a diffuser lens as you have done)
2. Unreliability (this is a more expensive light - £50 rather than £15 - and so may be better built)
3. Li-Ion batteries catching fire (perhaps you are paying for a better battery?)
1. Diffuser lenses help, but they aren't a complete cure. They do nothing about directing the light downwards, but just spread it out sideways so there's only half as much (?) going forwards. If the light is still being run at a high enough power (> 300 lumens or so), it will still dazzle.
2. Vantage's burnt out LED is fairly typical of the sort of failure you get with the actual light. There wouldn't have been enough heat transfer compound, or a bit of swarf preventing the mounting plate contacting the housing properly, or something similar. It is often possible to take the light apart and fix such problems before first use. The housing not getting hot very quickly when run on full power indoors is an indicator of a poor thermal path (don't try it for too long or you'll kill the light).
3. Batteries catching fire isn't common, but paying more isn't proof against failure. If it happens to Boeing, it can happen to anyone. Probably the best thing to do is to use the charger with it sitting in a heat-proof dish, such as a ceramic casserole, with nothing close by above it.