Hi all
I am making new orders from FT and INT but i am confused about the XPG2 from both sites, FT saying their XP-G2 R5-1A gives 472 Lumen and INT saying their XP-G2 R5 2B gives 558 lumens so are the 2 leds are different or one of the sites is wrong about numbers ? i know that 1A and 2B are different in tint color , i am comparing the 2 emitters only not the price nor the MCPCB.
R5 is the brightness bin. It's ranges about 518-558 lumens for the XP-G2. This is at Cree's recommended max amperage (1.5A).
as a side note: These are emitter lumens, so what you actually will get OTF (out-the-front) will be lower.
check out this site (wiki Cree XP-G2). Hopefully this helps with your future builds 
Thermal Management:
tech speak... if you can give your light a proper heatsink the copper Noctigon would probably be slightly brighter because it would keep the emitter junction temperature (Tj) lower.
In other words... Sufficient cooling capacity will help keep the die junction temp. lower... thus more output... especially as more time passes with the light on.
Die = the part of the LED that actually produces light. usually yellow and protected by a clear dome.