The Ease of Entry would benefit from just a one way ONTOP zipper, and it was considered...
But, i think that the idea for this bag was to make it just as Useable to a ground camper or tent goer and to Key in on versatility and Comfort.
We Liked the double sided 2-way zipper for a few good reasons.
1) YOu can Tuck the Lid or "Tongue" into the Footbox when you have the Sleeping bag suspended but do not want to cover up.
2) You can Vent from the sides and still be covered.
3) You can Hang your Legs out!!
And Lastly, You can Exit your Sleeping bag With the quickness if you need too, Just Push on the Lid and it tears away with out hassle..
What are your thoughts?