The High Drain batteries are a different chemistry. The are Lithium-Magnesium. Much safer and do not require a protection circuit.
They hold the voltage level of 3.7v until they run out. Other batteries start at maybe 4.2v and go down to 2v before they die out. So, your first vape is as good as the last.
Also, they tend to last longer and you can get more use out of them before they run out of power and need to be recharged.
All this, and they can use the regular multi-charger that other batteries use.
I think they are a great value in your Mods.
Hope that helped!