Well, yes, optimal can mean different things. 20000 lumens OTF is possible if they are driven optimally (BLF style), but I doubt they will be driven that hard for the reasons you mention.
The big difference between the single xhp70.2 and 9 x xhp35-HI is that the later will have a bigger hot spot diameter with the same, or higher, intensity.
The 12 x xhp70 will be another step up in hot spot diameter, but a bit less intensity.
In addition, the spill brightness will increase for each model as well.
The 12 x xhp70 also has the fan cooling to allow for higher sustainable output.
So it’s a matter of matching the light to your needs.
Who is going to get a MS12 to tear it down? What to know how they put the fan in.
Or does someone has a connection at imalet that can ask some details?
They better do so u can replace the fans, like olight showed incase they break down and it looked solid but for the production nope… because small fans arent really reliable in the long run, dust will collect etc if u cant take out to clean etc its a good reason why olight dumped such solution. And will manufacturer like imalent and acebeam have tons of stock of those fans in case they break down etc if u indeed can take them out urself?
Well yes but fans cant just be reliable for x hours, they must be reliable for many months or even years, i really doubt they will be and once again if not user replaceble then its just bad.
I think Imalent went with a cooling design that was very easy for them to build and it does not give high efficiency.
Acebeam designed their 40k lumen light using 3 fans for max cooling. Imalent has even higher output and is only using one fan (size unknown). It’s quite possible Imalent sped through the design phase just to get their light out onto the market as early as possible.