It cooks much quicker. I use a meat thermometer to check the internal temp of the turkey or chicken I'm cooking to check its progress. (I just stab the point of the thermometer through the bag.)

I disagree with above poster. I think it cooks quicker, as well as more evenly. I do take the bag off for the last little bit, though, to get the browning nice and pretty, so that adds some time.

The instructions are in the bag. It doesn't make it cook faster, just makes it cook cleaner.

Does the turkey cook quicker in it? I've never used one before but if the recipe calls for a 2-hour bake, do I have to assume it'll be less than that in the bag?