I’ve owned a few TM FNX’s, and most if not all airsoft red dots are hit and miss.
Either they lose zero eventually, or the dot stars out, or parallax error is really poor, or all three.
The TM red dot that came on my current FNX was so bad I gave it away
I use real steel ones now, best budget priced are Vector Optics
@MagpieTactical has a very decent one on his.
I have a Sig Sauer Romeo1 on mine
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