Even if you don't need the power of a VV battery they have addiional benefits if they have a screen and report the various levels (Voltage, Wattage & Ohms at least).
The wife has the Eleaf iStick 50W for instance which is always set at just 3.6V. When the coil starts to go the Ohm and Wattage readings will start to creep up until the limits of the battery are reached, then the Voltage will creep up to compensate. Being a non-smoker myself I can check the readings as I go past and know whether the coil needs changing or not.
The bigger batteries of course last longer, the little ego type ones needed changing every single day (and she's a light vaper) whereas the iStick can will last 4 days. I put one of her ego batteries on while the iStick is charging. They also don't look dwarfed by the bigger tanks such as the 5ml Nautilus.