2/8 #5
Shawn, acquiring 30 watt box mods seems to be a common desire these days....
I'll state this first: if you want pass-through, I recommend something with a built-in battery. I, personally, do not trust devices that charge/pass-through with removable batteries. I'm sure the electronics are getting better, but if something were to go wrong and the battery start to overheat, I'd rather ruin a $20 charger than a $50 mod.
This leads me to a first consideration: do you want (or even own) removable batteries? If you choose a device that uses a removable battery, you will need to figure the cost for at least one (I'd recommend two) as well as a charger. There are benefits and drawbacks to this approach, so you will need to factor that into the equation.
I week or two ago, in the other thread, I posted my decision-making process for one 30 watt device that I purchased, comparing it to a couple of others (you can find it
here). Since then, I know that Angel opted for one of the other devices, so perhaps she can fill you in on more about the device (mind you, it is the second version of the device that I looked at--that's how fast this industry moves). All of these devices have removable batteries.
For devices with built-in batteries, the only device that you could purchase today appears to be the iStick 30w. There is another device, the HeatVape Defender, which goes to 25 watts, but that's not much of a step beyond the iStick 20 you already have, so I doubt that would be of interest. I have both the iStick 20 and 30 and I will say that the 30w is better. Its biggest weakness, in my opinion, is the battery life: being the same size as the 20, it also keeps the 2200 mAh which could dwindle quickly with higher wattage vaping. For me, it is also just slightly (slightly!) too small for my hand (although, the plinth at the top does make it feel more comfortable than the original 20). That said, it is a pleasure to use and would make a great traveling device.
If you wait for a week or so, there are two other devices that may be of interest. The first is MVP 3.0. The MVP2 was a stalwart device for many of us over the past year. The MVP2 is literally built like a brick and provided a large capacity battery combined with steady power. The MVP 3.0 improves on this, bringing to the table 3800 mAh, the ability to hit 0.4 ohms and 30 watts, along with the ability to charge other devices like cell phones. Based on the track record of the MVP2, this should be a reliable device. It is larger, though: the older model is 9.5 x 4.0 x 2.0 cm and the newer model is larger.
Another device around the corner is the iStick 50 watt. While it has more power than what you're looking for, it is the same basic shape as your iStick 20--just larger and with a second rounded edge, with a trigger-like fire button. This device also comes with a 4400 mAh battery as well as all the improvements brought to the line by the 30w.
I am actually considering both devices for purchase: the MVP for my desk and the iStick for portability. But that's just me.
Hope this helps. I'll be available later this afternoon on the other thread if you have questions.