Thank you for this feedback.
I think I'll take a 52.
For the color, apparently not many people chose the Chameleon 08HS or Chameleon 13HS colors.
Yes, I'd recommend go a bit smaller. Also as regards stem length please note that it's measured from below, hence a 100mm is actually a 110mm.
As regards colours, I recommend you to go wild
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After all what's it worth to build sth custom if it's not unique