Yesterday I received my third Surface Pro 4. Not that the others were defective, but due to some Microsoft incompetence haha. So, anyways, The other batches were 1545, and this one is 1547, and I think it's a better batch. Battery lasts longer, no doubt. But it could be the software loaded upon arrival. I decided to do the passive updating method, and I have had it for a few days and it hasn't updated a single update as of yet.