Well I thought with more people at least we can exchange drivers so it won't be as tiring, and in spring or summer then there's no subzero problem, not sure about weather delays.
For this January trip I do have time constraints, hence gotta drop the idea of driving.
My neighbor did drive from Seattle to LA with rest area stops only, several times per year, not sure how he deals with the subzero problem, probably it was not in cold winter, and I know it's shorter distance too.