Someone mentioned the 6 day drips. Yes, they are painfully long. Halfway thru, you won't believe that there's still a whole 3 days still left. That being said, when you get back to the US for your mid trip layover, you're at the hotel in the early to mid afternoon, and pick up the next day is not til 5pm or so the next day. This becomes the guaranteed opportunity to cash in on your "sleep debt" and then some. The next morning (or afternoon) you wake up feeling great. Throw in a workout, plus a big breakfast and you're completely recharged come pickup. But yes, you will be thinking, "damn, got 3 days more to go"