On your "B" route, you'll hit some lane closures and possible delays due to scheduled construction and some damage from Irene & Lee on I-88 between Binghamton & Sidney, NY. It is, however, open and passable,
I have run both routes fairly often. Coming all the way East to Newburgh to hit 87 seems out of the way for me. It also means more toll mileage. Another poster says I88 is open again after the storm. That is the way I would go.
87 Mallard Sprinter 24' Class C Ford E350 w/460 gas "The Runny Duck"
Shiny side up, Rubber side down.