If I were you, I would pop over to Liberty Flights, get a cheap vision spinner variable voltage device, ego style, and try and see if the whole vv thing works for you, you can get a discount from the discount code page here, it is POTV, that will cut the cost further, or LF have a daily discount code that they will usually post on their facebook page which can vary, so will sometimes be as high as 30% off, not often that high though.
Then, if you like that, go for a vamo, vv and also variable wattage, a nifty device that can cost between £33 and £44 depending on where you buy it, and whether you need just a body, or a full kit, which will give you batteries and a battery charger as well, Vaper Train and esmoke uk are two example of places to say, go for kits, vapingthings, where I got mine, do just the body for £33.
Just look around, at the discount codes page here, the vendors section too, and google some youtube device reviews, I'd say, and hello.
Edit: Straight up variable voltage will give you warmer vape at higher volts, but for a low resistance atomizer say, that could burn your juice, or blow your coil, whereas variable wattage is less likely to do that, as most vw devices will detect your ohm resistance, and adjust accordingly.
