Recently received a hand-me-down red dot site from a friend. Up until now I've just been using the irons and have been very happy with them. I've never used a red dot optic before and wanted to know if people had different opinions on how far forward or rearward on the rail it belongs.

Is it purely a matter of preference and comfort? Does it depend on the distance or style of shooting? Any advice or opinions are appreciated.

Thanks all.