As per the title, what’s the difference between the 2 and if it was the exact same torch but with the different LED’s would there be a noticeable difference or would it be so marginal you wouldn’t notice it???
Q3
LEDs are graded (binned) by tint and output. The output ratings are ascending by letter and number so a Q5 is brighter than a Q4 and an R5 is brighter than a Q5. Each bin lumen rating is plus or minus 7% or ~ 15% greater than the one below. That variation also means that a Q5 could be anywhere from just over 2 bins higher to just under 4 bins higher than a Q2. The human eye discerns brightness in a non linear fashion so for an led to seem twice as bright it has to have several times the output. Side by side you can easily tell the difference between the two bins but the difference won’t seem as great as the difference in lumens would indicate. We’re mostly lumen junkies here and always looking for a few more whether we can see them or not but I’m sure most of us have at least one light that isn’t maxed out. What the bin really tells you is how efficiently the led converts power to lumens. White LEDs start out with a blue die that is coated with various phosphors that absorb some of the blue light and re-emit other colors that blend together so that we see it as white. Cooler tints have fewer additional phosphors and are brighter but bluish while warmer tints use more additional phosphors and result in lower output. The highest output bins are always cool white.
Are you talking about Cree XR-E?
Rufusbduck … cheers for that 
will34 …… I’m not sure what the XR-E means ? it’s in relation to one of these which comes in both Q2 and Q5 …. although the Q5 is harder to come by and double the cost and I’m trying to work out if there’ll be any / much difference between the 2
http://www.kaidomain.com/product/details.S008589
Cree XR-E is the type of LED and Q2/3/5 are the bins/levels as explained by Rufusbduck.
The XR-E is a very ancient LED and is only good for ~200 lumens. My last flashlight with this emitter was bought in 2010.
Any particular reason you want to spend your money on such an old flashlight? you can get much better lights for the same price…
To answer your question, you wouldn’t notice difference between Q2 and Q5 since it will probably be something like 170 and 190 lumens respectively.
will34,
I believe this torch has a very narrow focus which is specifically what I’m looking for …. something that focuses down narrower then say a SK98.
The SK 68 is the perfect size focused but it eats batteries, I’m trying to achieve exactly the same but hoping that an 18650 as opposed to a 14500 will extend the run time.
de-dome an xpg-2 or an xpe in an 18650 light with a bigger aspheric