Deep reflectors (compared to shallow reflectors of the same diameter) produce about the same spot brightness but with larger spot, at the expense of spill angle (and it lengthens your flashlight). I like that for a thrower.
It seems they never learn…
The gaps in those fins are actually not small if you pay attention. I think it is more than adequate. But that flashlight must weigh 20lbs and doesn’t seem very wieldy. Wonder what the throw is. 5MCD? Would be cool if they can make a RLT collar and aspheric lens to turn it into a 10MCD Enderman light. Under $600 would be a bargain if it makes more than 6MCD.
The gaps are relatively small in relation to their depth.
This means very little airflow between the fins.
The BLF / Lumintop GT has proper fin spacing and not too deep grooves either.
Right.
What matters is proportions and these are not good.
The BLF GT90 proto is here at 1.8 Mcd, coutesy of Matt (VOB): https://www.youtube.com/watch?v=xQBDrNKyWKY, and here: https://budgetlightforum.com/t/-/59967
Not a significant improvement in throw over the GT (XHP35 HI), he tested at 1.5 Mcd. More lumens of course.
this led screams for a GT4 host.
This led screams, current give me more current!
Impressive though, the GT90.
Does cree have plans for a XHP35.2 ?
It’s going to be expensive with … 4 SBT-90.2’s Then I’m going to want an extension tube (4 carriers) so I can have a battery carrier for each LED… It’s a very HUNGRY LED… 
Yes please… :+1:
Can I simply flow the 90.2 on to the existing ft03 board and will it work like that?
No, it’s a different footprint. It’s similar to the Cree MTG footprint so you can use those MCPCBs.
With such an expensive emitter I would prefer them pre-mounted. Tom E wrote “They come pre-mounted on a 20 mm MCPCB, $36 each.”
I wasn’t able to find any details on lantend.com about that. Has anyone received any pre-mounted yet?
Yes that is probably an option. For me by default they came bare. I didn’t know the quality of their MCPCBs or their reflow, so I figured I would rather get them bare. Have to check with Tom E about whether he got them on MCPCBs.
So where can i obtain one of these LEDs for a reasonable price?
Or do i have to buy a complete NI40 light?
You see, i have this ginormous GT flashlight here, and the XHP35 HI is just too small for it.
If i could get a SBT-90.2 for it, it would be awesome.
I’ll worry about the driver later.
Maybe the stock driver could be adapted with a stack of FETs, a huge toroid coil and fat flyback diodes.
SHouldn’t there be a group buy for these LEDs?
The one place lantend is the only source right now as far as I know.
They are $35 each, and unfortunately shipping (DHL) was $40.
Thanks, and i could have found the answer on the previous page myself… 
I read they only have 5700K in stock, which is rather cold for my taste.
4000 - 4500K would be awesome.
I would buy several and re-distribute them myself.
Your GT does not just need a new driver, also the battry carriers will have to be converted from 4S to 4P.
With a buck driver mod i would need 2S2P (x2)
But i haven’t seen any Voltage / Current tests of this LED, so i assume the Vf will be above, say 3.7 volts when pushing it to its limits, which is a bit high for 1S4P (x2) i.m.o.