DNA 30 is a solid device, but quickly becoming old tech - I'm expecting a new DNA chip to be announced in the next several weeks, as they're cutting prices and clearing out inventory.
The Subox is tempting - Kanger generally puts out a good product, but you'd essentially be guinea-pigging it yourself hopping on board this soon. I waited until the Kbox had been around for a while and loved by everyone before I jumped on that one (scored a couple for $12 each, crazy good deal) - I like it, though the spring needed to be filed down to take off a sharp edge that was digging into my battery's negative contact. I'm tempted to go for the Subox, but I just bought some new mods with the Kboxes (and an iStick 50 that blows goats quality-wise), so I'm going to stop spending for a few months...
What kind of toppers are you going to put on whatever you're buying?