@mardah oh... you mean pin change system, not extint. You can use it of course.

@GertSanders ok, strange. standard pin headers fit for me only into FTDI and ICSP pin holes. Into the other two 8 pin rows it does not fit.

@scalz Thanks for your answer. Assembling a sensor by my own is not really what I want (or am able to achieve). So buying assembled sensor is the only option for me. Thus probably commercially available sensors will fit better, since they can use the scaling factor of assembling a huge amount of sensors. My HA is driven by cost to performance ratio, where cost also include somewhat the amount of time to invest and performance also covers things like the ease of use, appearance etc. Interesting to hear though that those commercial sensors might be less premium regarding the part quality, battery life etc.

@JahFyahh - I still haven't managed to et round to it. I've been really busy since this project and its still hectic here. I'm sure i read a few reviews somewhere, here or google. Not sure.