That is the nub cooler from Lamart, it fits the Milaana2 but NOT the Milaana3
You will want a external charger with digital screen to show you charge level, 4.2v is fully charged and usually stop at around 3.7v, he will be able to sense the battery level the more you get used to using the Milaana since being unregulated the power (speed to heat up) is dependent on the battery charge level... so fully charged it will be very hot and fast that you hardly hold the trigger at all, whereas a low battery will require you to hold the trigger longer...
High output means it naturally runs hotter and faster, so greater battery efficiency, less time on the trigger needed... This is the one I have and the one I would recommend, the low output you have to hold the button a lot more and you will get fewer bowls... The high output could have a little more learning curve, but overall it's the way to go for me... You can expect a minimum of four bowls, and potentially up to eight probably depending on your usage... (low output version's battery life is probably more like 4 bowls max, 3-6 perhaps)
And yes absolutely great for everyday use, just could be a learning curve depending on what you are used to, but the more time you spend with it the more it will feel like second nature. It is a very simple, pure, powerful, beautiful, and versatile device!