title_body: In home roasting, does the time spent roasting matter, or only the final temperature?
upvoted_answer: It does matter for a couple of reasons.
  
  Drawing out the roast generally produces more even results.
  
  Slower roasts mean that you have a better chance of stopping the roast at the target level and not over or under roasting.
  
  You can search the online forums for some of the home roasting sites, but many people run their roasters at a higher setting, then turn down the heat once the roasting process is rolling.  Some of the more expensive machines even have "roast profiles" preprogrammed to modulate the temperature up and down for desired results.  
  
  Personally I think there is a point of diminishing returns between the time dinkering with the roaster and the difference in the taste.  Most of my roasting lands in the 15 to 16 minute range and comes out even enough that I feel good about it.  I recommend drawing the time out just enough that the results are even enough for you and you are comfortably hitting your target roast level the vast majority of the time.