I usually like to mention a reason for closing which I forgot in this case.
OP, this topic has been beaten to death. There are probably 30+ threads on this topic. I am usually the last person to point someone to the "search" function but for this topic, seach is your friend!
Stick or Automatic
http://www.the370z.com/nissan-370z-g...automatic.html
http://www.the370z.com/nissan-370z-g...tomatic-z.html
Manual vs. Auto performance