I'm not going to get technical, all I will say is that it's Smok. They have flooded the market with mods and tanks but taken no pride in their coils.
I have multiple Smok devices, tanks and RTA's/RBA's and the only thing that holds up are RTA's/RBA's.
They also have a slight tendency to leak.
With Aspire tanks I have no problem with sweet juices and get an average of 5-7 days from a coil although I have read many reports of people having issues with sweet juices with a lot of tanks.
Best advice I can offer is to try an Aspire Pockex, I doubt you'll look back. I think they sell for around $20-25 depending on where you look.