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.
“If you don’t know who I am, then maybe your best course would be to tread lightly.”
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