They just started carrying them like the 23rd of Dec this year. I did get one and it is well worth the investment. This would be my go to system if the carts were more easily attainable. Loads of thick vapor - solid feel - battery lasts more than a day, longer than the 808D-1 (4 hours), 510 (2 hours), and 401 (90 minutes) systems. The e-juice it comes with isn't so hot - but then again I prefer the food flavors only available on the net.
My 808D-1 chargers and carts do work with it - but there is a gap using the d1 carts. I do prefer the D2 carts because they hold more liquid. I've only found 2 places on the net that carries these carts for a somewhat reasonable price. I'm not going to pay the ridiculous price of $15 for 5 carts that wal mart wants because its too expensive and I'll have to empty their juice and put mine in which is an extra pain.