IMO, it depends on how important a crispy skin is to you. At 250, the skin will be a little "rubbery", which is why I just remove the skin if I am smoking turkey breasts for sammich meat.
If you want to keep the skin, I'd go for 225-250 for the first hour or so, then crank it up to 325-350 to finish it off and crisp up the skin. Or just run it 325-350 for the entire cook, I've done both and both have come out juicy as long as I've brined it.
Shelter me from the powder and the finger
Cover me with the thought that pulled the trigger
Think of me as one you'd never figured
Would fade away so young With so much left undone
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