that was quick... some people wait months before pulling the trigger
I have not used Blizzak's on a truck, only cars. I can tell you they have a funny feeling when you drive them. Car and Driver described it as a squishy feeling. It happens from riding on the tall, soft treadblocks. That info came from a review of the old DMZ3's. Going down to a 245/70 is almost an inch narrower and will have a different contact patch. This will sacrifice a little lateral stablilty, something you will definitely notice and I don't believe you will like. I'd recommend the stock width.
Nokians drive a lot better. You will pay more, but IMO it's worth it. Full siping, full depth high traction compound, better mpg (Hakka R- suv), Hakka siping. Plus you can choose from several different snow tire options to best fit your driving.
Hakka SUV
Hakka 5 SUV
Hakka R SUV
Hakka LT
I'd say the more open tread pattern tires will do best in slush. That would be the Hakka LT. I know that the grooves in my Hakka 5's are "polished" to allow the snow to clear the tread more easily. I have driven 2 winters on them, including wet snows of march-april, safely, with little tire wear evident.
I'd think a little longer and balance the safety vs. price pros and cons.