I've played with the IPV Mini V2 and an Arctic tank at 60 watts and loved that setup...it was what I got my friend into since I don't need another mod and I wanted to try it and see if it was any good...i will tell you my friend is a clutz, we had to find him something that could take some abuse and so far the Mini V2 is holding up like a champ....he also got a Segelei 100 watt V2 and managed to destroy it the first day to give you a reference point of it's durability. The Yihi chips are great but I will warn you that their output is a bit off at the higher wattages, I just posted a thread about it here....
http://vapingunderground.com/threads/segelei-150-and-other-sx-330-mods-voltage-off.81521/
But at the output range of the mini it's not really a big deal, just something to know if you're looking at a IPV 3 or a Segelei 150 for the future. Also, the Yihi chips don't seem to have quite the efficiency of the evolv chips as with my DNA 40 set at 25 watts I can get 2 tanks easily out of my Subtank mini with a .5 ohm stock head.
Also, just for information because I saw it discussed earlier in this thread...the dual battery SX-330 mods are series mods because you simply cannot (at least safely) power a regulated mod that puts out more than 60-70 watts with any single 18650 battery we have available to us at the moment. So to solve this problem they run two batteries in series and then step down the voltage because with higher voltage you need less amps to produce the same amount of watts.
Running a dual battery mod is parallel effectively gives you twice the battery life as well as twice the continuous drain limit that you would have with the same mod only running a single battery but it's max voltage output is still 4.2 volts. For example, if I am running a mod with 2 Samsung 25R's in parallel instead of getting 20 amps continuous drain at 2500 mah, I get 40 amps at 5000 mah because I am effectively splitting the load between 2 batteries and since they're sharing the work load each battery takes half of the stress applied to it.
Where as running batteries in series I only get double the output voltage. So if I am running the same 2 Samsung 25R's in series I get 20 amps continuous drain at 2500 mah but with a voltage output of 8.4 volts. Running in series doesn't really give you extra battery life like running in parallel. It can give the appearance of it with some regulated mods as the mod is stepping down the voltage and with the high voltage output you might not be pulling a lot of amps out of the battery so it gives the appearance of a longer run time (ie.... a 1 ohm coil on a device that is 90 percent efficient running at 40 watts and 4.2 volts draws 10.58 amps off the battery, the same coil drawing power from 2 batteries in series draws 5.29 amp at 8.4 volts. Because you have twice the voltage and half the amp draw it gives the appearance of longer battery life but in reality two batteries in series last the same as a single battery and a mod running in parallel will last twice as long as the parallel setup has twice the mah to do the same a single battery setup. Running batteries in series is also more stressful on them as one works harder than the other and that's why the should be rotated every charge...but I am getting sidetracked) Also, because these mods are regulated by a chipset, their battery configuration isn't the only thing determining their lifespan, the chipsets efficiency plays a big part in it as well.
Just some useful info to have, the bottom line and all that aside, I give a +1 for the IPV mini v2, it's a tough little mod that gets the job done. Oh, someone else touched on it, but the reason why it's better to take the batteries out and charge them on a good charger as apposed to a USB charger is that a good intelligent charger will monitor the batteries as it charges, makes sure that they are properly charged, and some of them won't even charge a battery in to bad of health...as apposed to the little USB charges in the mods that just know when to start and stop the charge. Also, some people mistake the onboard USB charger port for giving the mod a "passthrough" option (being able to vape the mod while charging,) were the mod's chipset might not have the software written into it to incorporate that feature and trying to drain the batteries while charging them can cause problems...there have been issues with this in other IPV mods so despite the PITA it is I would recommend always charging the batteries on a good solid charger...and if you're feeling handy...with a drill and about 4 bucks worth of rare earth magnets you can convert the back door to a magnetic instead of screw held one...
Happy vaping and cheers!
