Today I'm trying to install Banana Pi M2 zero instead Raspberry Pi Zero W. 

Here a quick comparison:

I've tested real speed in different applications and found that Banana PI M2 zero is around 2 times faster than Raspberry PI Zero W.

But M2 has one problem, it dissipates much more heat than PI Zero....

My enclosure is small therefore I need a big heatsink for M2 processor and memory cooling, also I need to create special profile on the bottom of the heatsink (because of some components more height than the processor and memory). 

So I found old heatsink from the computer PSU, cut piece from it, machine bottom on the CNC and glued it right on processor and memory ICs. 

The whole sandwich looks like this:  

Now it's time for the temperature tests. I will tell about the results next time. Stay tuned)