I don't want to be busy babysitting it on Purim which is why I am going to try it sous vide.
Alternatively, you should get a PBC like I have, and never babysit again. I told my wife, the day it came, that I'm never babysitting again.
Here's my smoking schedule for Purim.
Come back from megilla at around 730. Light smoker, make rub and rub brisket, hang at roughly 8.
Go do whatever I do.
The smoker will cool off at about 2, and its cold enough outside that it will be fine. Brisket will be right around stall then, so it's perfect.
In morning, wrap and put in oven at 225 until thermometer hits 203.