Is there a difference in quality of using a plastic/wood/metal stirrer? I happen to see in more commercial coffee shops that stirring of coffee for Lattes etc. is done with a metal spoon, however when I order a plain coffee and go add milk/sugar there are plastic stirrers. Similarly when I go and have coffee at work the office has wooden sticks to stir the coffee. 

Besides for sanitary reasons, does the type of stirrer used effect the quality of the coffee? Is there an "ideal" stirrer material when preparing coffee?
I'm just reasoning...

Polished gold or porcelain must be the ideal stirrers as they won't chemically react. I opt for porcelain as it may also help keeping the coffee warm as its thermal conductivity is less than gold.

Comparing the three you mentioned:


Wooden: Sometimes I taste it. So, I don't prefer it that much.
Plastic: There are many polymers we call plastic in our daily life. Some of these things are really of bad quality and I am suspicious if their thermal resistance is adequate for coffee. I wouldn't prefer them, too.
Metal: Especially, if you mention polished 18/10 stainless steel cutlery, they probably resist the heat and won't react with anything. So, the only bad thing about them is, they may make your cup colder a bit quicker than usual. Just take the spoon off right after use. This would be my preference.