Some nights you won't observe at all if your only choice is to assemble and collimate a truss scope.
I don't know if that assembly of a truss is so bad. Mind you - lol - I've never done it but if you figure that first hour the mirror is cooling down anyway who cares if your putting it together and how long can it take at most 30min? I'd bet half that without collimation - I'm thinking of a 12" f/5 truss.
You care if you don't have the 30 minutes to spare. A scope cooling down does not require human intervention; I can be cooking, eating, cleaning, etc. while the scope is cooling down. I cannot do those things and assemble or collimate a scope at the same time.
I typically stick my Z10 out on the deck, plug in the fan, and come back inside. It takes about 2 - 3 minutes. Then I wait an hour for cooldown and do my other tasks. After dinner, the scope is ready.
Some nights you'll have time to assemble and collimate; some you won't. I agree with the poster who said that if you can leave the truss scope assembled in a shed or garage, the problem largely goes away. And I agree with Jon that a 4" refractor would be a great companion scope.