The Fenix LD40 is a solid light for outdoor or general use. It runs off of AA batteries instead of more exotic lithiums like many high output lights. It also has a relatively large reflector, giving it nice throw for a AA powered light. The LED is a neutral white instead of the typical cool white, giving you better color rendering, which is great for an outdoor light. Greens and browns look more green and brown instead of the washed out colors that a cool white LED gives, but it comes at the cost of a slightly lower output.
The body of the light is plastic, which is an underrated feature in an outdoors light. Metal bodies can be friggin’ cold if you are not wearing gloves, but if you are using the light in cold weather, you need to make sure you are using Energizer lithium batteries or similar ones that have decent cold weather performance since alkalines will crap out on you, if they even start the light in the first place.
My favorite feature of the light is the addition of a second switch on the tail, giving you one handed access to power the light on and switch modes. Dual switches means that you have access to momentary on, which can be very useful, while still having the consistency of a switch that will not switch modes while rapidly using the momentary function. The regular flashing modes are there as well in case a bear gnaws off your legs and you need to signal SOS to a passing hiker.