I've misplaced the box my Nautilus came in, so I can't check the serial number. My problem hasn't been with the atomizer, but with heads, many of which don't last but a day or two. I've experienced the good heads that last well over a week.
Lately, my problem has been heads that don't last a day. The failure mode is sudden loss of vapor. When you check the resistance on your mod or with an ohmmeter, it has suddenly gone high. I went through 3 coils day before yesterday that now read 2.9, 4.0, and 7.4. 2 of them lasted a couple of hours and another lasted a day before entering this failure mode. When the low vapor problem starts the head may read 2.4. A few minutes later it will read over 3 ohms. Not long after that it may go to 4 or 5 or as high as 7 ohms.
My Nautilus heads come singly from my B&M. They are in a plastic bag with the head contained in a rectangular bubble pack with the Aspire logo on the foil cover. They don't sell 5 packs at my B&M.