color fiber laser marking machine price /fiber laser engraver/laser marker on metal

Product Overview
1. There are 1ow/20w/3ow/5ow ,which power should l choose ?
Common Fiber Laser Power 10W/20W/30W/50W ,The bigger power,marking efficiency would be greater.--20W fiber laser engraver is the most pop choice.Basic 20w fiber laser can meet 90% work.
--10w is good for shallow marking work.
--30W for some deep engraving, or match with big size F-theta lens for big size marking.--50W for some deep engraving or high precision thin thickness cutting work(O-0.5mm).The bigger power,price would be higher.
Your machine model is equipped with 20w
@2.There are many sizes for the machine,which size should l choose ?
--SF110 110X110mm Small size, Deep engraving.
--SF160 160x160mm Standard device for Smartech.--SF300 300x300mm For big size engraving.