I'll probably get Duratrac too.
For both on/off road and winter
I can't afford switching them and more than that, i wouldn't have space to store them
In my case, i'll switch the rims with some 15" steel rims (or most likely 16" because of bigger disk brakes on Sahara).
They steel ones are be better offroad
as i already damaged the factory ones on some trails ...
And about the `bigger tires` my Sahara came with 32" tires (255/70R18) so without any changes you can go up to 32" without problems.
I know somebody running 33" with minor rubbing offroad.
EDIT: and if you find a good deal on your new tires, please let me know
I live in Montreal so i'm be interested.