I have the Magma and the Inferno
They are both solid versions of the mini 510 and the large mah 510's
The warranty is good, I just had my first opportunity to test it out when my Inferno died on me 6 months after I bought it, they replaced it and payed for shipping.
I have actually been using my magma a lot lately, in fact in the last
three days I have not picked up a
mod or an ego/leo/riva/inferno other than for testing juices.
I would stay away from the volcano/ volcano super mini- but thats just me as I don't like the blu style units.