The beam does tend to look a little tighter with a 50 vs 70 because of less spill, but surface brightness of the dies is actually about the same so, to a lux meter there would probly not be much change.
As for the heat. Yes, it would save on heat IF the drive current was reduced. If the drive current remains the same the 50 will run hotter. Case in point I tried this with my copper P60 bulbs. At the 6-7 amp level the 50 got hot much faster and produced less light.
The main advantage of a 50 vs 70 is cost per emitter, and ease of mating with existing reflectors and mcpcbs.
Personally I would be more interested in the 70.
VOB what driver were you running in the P60?
I built a JAX x6 hunter with a XHP50 driven 4A and wasn’t impressed with the output, doesn’t seem like a major improvement over my YEZL Y3 MT-G2 2.4A, so I agree going big is the only way 
Thanks for all the info. I’m really excited for this one, particularly the clear anodized version.
It’s me again. The head and reflector size of the L6 was brought up in the L2 thread and I got a response from Simon so I figure I should post it here too.
The L6 head diameter is 72mm and the reflector diameter is 65.48mm
oops, I forgot there was already an L6 thread. That explains why there isn’t much info in the L2 OP!
Do we know how heavy the OP will be on the reflector? Was there another reflector he was using to model his OP after?
You and Dale are killing me! 
Keepin ya awake, that’s all, making sure you’re crossing your t’s and dotting your i’s and minding your p’s and q’s. (you DO know don’t you that minding your p’s and q’s comes from bartending in the old days in Europe? You have to take good care of your pints and quarts, bottoms up!)
Hey! - I’ll Drink to that!
Only 20 more, Dale… Keep talking!
-Chuck
I’ll take a Pint to Go
A pint sounds great right now but I think I’ll have to settle for going to bed. Keep on spewing your alphabet soup Dale! You could get there tonight pretty easily. How about a couple poems off the top of your head?
Here? :bigsmile: You know I want the slightly bigger (L6) smooth reflectors please!! Small emitter hole will work for me too! I like fitting them to the die of the XHP70. Since I want (2) L6’s, I’ll need (4) smooth reflectors. Thanks “J” :bigsmile:
This will be a JAX X6 Hunter killer, and I'd think at a lower cost 
.
That’s the plan man!
Money is ready, just say when J-Dub74. J)
+1! Any idea on a time line for the L6?
Hopefully Simon added a few exterior cooling fins below the emitter shelf? It was the main thermal bottle neck when running a XHP70 on 1.5mm of added copper, in the L2, at 10.4 amps, the Lumens were dropping like a rock at 15-20 seconds. at 1 minute it was seriously uncomfortably hot!
Killer of hard driven XHP70 emitters and batteries maybe? This was discussed in the L2 thread. My X6 XHP70 pulling over 11 amps on 2 26700 Imrens gets hot fast too, but outside comfortably warm at the 180 second turbo timer- no problem. I just keep popping back to turbo.
Oh boy, but in shear size, the X6 is bigger than an L2, but the L6 will be darn close to the X6 in size. But from the pics of the L6 in the OP if they match what will ship, there's lots of metal there but not as much finning as the X6 in the reflector base area, critical LED area.
Correct! Actually the X6 is massive in the head area, way heavier than the L2 and possibly the L6? I’ll find out? But lack of cooling fins not in the X6 more would be better but I can make this work. It also has the small area between head and reflector. I made pressed fit copper pills bored out the threads,.001” press. for more area and contact with the host. The new Maxtoch 32mm XHP70 boards are just kick ass too. It’s all about the design really,when all my X6’s are where I want them, I plan on potting the inside between head and reflector, with what Randy Brogden (PFlexPro) use’s Stycast Thermal Epoxy potting compound. I will try it out on one light first. It’s quite expensive but worth it to me if it makes and it should, a difference. It’s not all about light box readings and amp pulls with me, I actually use my lights and let other fellow hunters and trappers use my lights for real world testing, will it live? Randy Brogden,Dale and FP opened my eyes to a whole other avenue of modding. Making it LIVE! :bigsmile: