Has anyone used this new sheathing called Zip panels? They are osb sheets with an airtight coating on the outside. You tape the joints with their tape and they say you don't need housewrap. They have a thicker panel of the roof that works the same and doesn't need paper under the shingles. Costs about 11 or 12 bucks a sheet.
It's made by Huber. The same copany that makes Advantech floor sheathing. I have been using that exclusively for 5 years.