Hi mels. For a few dollars more you can get the iStick 40 watt 2600 mah (which has temperature control if you want to use it).
http://www.myvaporstore.com/Eleaf-iStick-40W-TC-Kit-p/elis-is4070.htm The IPOW 2 is a 1600 mah.
I'd recommend the Aspire Nautilus Mini for a tank to use with the iStick or IPOW
http://www.myvaporstore.com/Eigate-Aspire-Nautilus-Mini-2ml-p/ap-mna-k.htm and you'd need a few extra coils (they last from 10 days to 2 weeks on average)
http://www.myvaporstore.com/Atomizer-head-for-Aspire-Nautilus-BVC-V2-p/ap-na-2ah.htm
It would look very similar to this pic
Buying online is usually 4 days shipping in my experience. You might try looking here :
DEALS and STEALS -
https://www.e-cigarette-forum.com/forum/threads/deals-and-steals.418767/ (go to last couple pages)
FORUM SUPPLIERS -
https://www.e-cigarette-forum.com/forum/suppliers/
COUPONS -
http://www.e-cigarette-forum.com/coupons/stores/
I had a similar battery like the IPOW, but vape really shined with longer battery life and the ability to fine tune the coil/tank.
Aspire Nautilus on the Spinner 2 (center) and iStick 50 w on right.
Good luck in your decisions and enjoy the vape journey.