The Istick has the same limitations as the DNA 30. 4v minimum. Most people that buy a DNA 30 device knows it doesn't step down but the average Istick buyer doesn't and some complain about it. The Istick does Vavg rather than RMS so the 3v Vavg (Mean) is actually closer to 4v. That's why I vape at lower wattages on the Istick.
I just called the shop and they sold their last DNA 30 a day ago. Whew, dodged that bullet

. They did say that they should be getting the rDNA 40 next week sometime.
If you want to save a few bucks, Focalecig is having a group buy on their Hana clone made by KSD for $37.90. It's shipping from China so figure about 3 weeks. They have a US warehouse that has a silver for $45 and black for $48. There is a code for 10% off but it doesn't work for stuff in the US warehouse (code: fcvapingcheap)
Focalecig -Best E-Cigarettes - Worldwide Free Shipping
$42.27 (Ship from USA)HANAA MODZ DNA30 Mod - Silver(18650)
$47.27 (Ship form USA)HANAA MODZ Pack DNA 30 Style Mod - black
I ordered a blue one from China so I can mod it. $43.99 shipped.
I should mention, I found out that this clone might still have the pause to fire from sleep issue. I say "might" because the guys I've heard it from ordered theirs a couple of months ago.