LD41 vs M40a runtime difference question

Lights have different efficiencies and different output patterns. Let's say Light A starts at 1000 lumens, then drops to 500 lumens after ten minutes and runs for an hour. Light B starts at 1000 lumens, holds it steady, then dies after half an hour. Both lights would claim 1000 lumen output by the ANSI standard, but light A would have twice the runtime.

Find a review with a runtime chart...but really, almost everything is more important. Which UI is better? Which looks nicer? Whose beam pattern is preferable to you? Whose warranty service works better?

That makes sense. Before I wrote my post I found a runtime chart for M40a (in a selfbuilt review) but could not find one for the LD41. The M40a seems to have a very stable output for the duration of the runtime. The M40a looks better IMO, and from all accounts seems to tailstand better, the LD41 being a bit wobbly. Despite the M40a being a little more expensive it seems to be my preference.

I dont expect to use the flashlight on the highest setting for long periods anyway.

The m40a has a magnetic control ring for the choosing your light brightness lxevel which i heard isnt the most efficient switch out there. The biggest difference is going to be in how far they throw. The m40a has a higher lux reading and will throw further than the ld41. Also note the new upgraded m40a has the u2 xml led and is rated at 645 lumens. I just checked and the m40a is good for 1.5 hours at high. I own the m40a and really love it. Great build quality and very bright using only 4aa batteries.

T-roc87 said:

The m40a has a magnetic control ring for the choosing your light brightness lxevel which i heard isnt the most efficient switch out there. The biggest difference is going to be in how far they throw. The m40a has a higher lux reading and will throw further than the ld41. Also note the new upgraded m40a has the u2 xml led and is rated at 645 lumens. I just checked and the m40a is good for 1.5 hours at high. I own the m40a and really love it. Great build quality and very bright using only 4aa batteries.

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I was looking at the canadian distributors web site which shows the older LED and shorter run time. i will email them to ask if they will fill my order with a light with the xml u2 LED.

The m40a tailstands very well. Also note that selfbuilt reviewed the m40a with mc-e led which is a much older and less efficient led than the xml t6 or u2. Even the t6 xml is rated at 1.5 hours. The xml is much better led which really gave the light a boost in throw as well.