Okay, so I'm new too. I have tried the Aspire CE5-S, and the ET-S. I like them both. But the winner of those two is the ET-S. I have read and viewed rave reviews of the Aspire Nautilus Mini, and I just ordered one this evening. It IS different than the bigger tank, because the coil is different. At least that is my understanding, it isn't just about the size. The CE5-S is fine, but after using the two cheaper ones, I prefer the ET-S. That one cost me 14.99 at the local store. The CE5-S was about 8.00 or so. I just ordered the Nautilus Mini from CJ Vapors in WV. They also have the replacement coils, and I bought some for all 3 tanks. (the CE5-S and the ET-S use the same coils) It is a shame the Nautilus Mini doesn't also use that same coil, then I could buy a little stock of them. The kicker for me was watching some You Tube video reviews of the Nautilus Mini. Some very well known folks gave it a huge boost and two thumbs up. That was good enough for me.