Selecting the right surface finish

Selecting the right surface finish Door: Eurocircuits N.V.
Use the wrong Surface Finish and it you may have downstream issues during assembly or longer-term reliability issues.
But how to make the right choice? For this weeks TECHNOLOGY THURSDAY , we will help you answer this question!
What are the options?
HAL Leadfree
+  the highest level of solderability
-  not the best choice with small via holes or when the board exceeds a normal thickness
Chemical Ni/Au
a flat surface, good solderability and acceptable shelf life
complicated with a higher risk of defects, expensive and not for applications which are subject to shocks, bending or strong vibrations
Chemical Ag
+  a flat surface with very good solderability
-  susceptible to sulphur dioxide (SO²) which tarnishes the surface and creates the AgS² layer
What would you choose? 
Enjoy your day !