there seems to be a lot of knowledgeable replies here but my own 2 cents on the matter, being an ex-smoker that strictly vapes now, is: the juul works. the other e-cigs i used helped turn me on to the idea of vaping instead of smoking but the juul is what sealed the deal. my own experience. maybe yours will differ. but the simplicity of the juul really did it for me. that and the accessibility. they sell them at gas stations here so there's always somewhere that has them nearby. pretty much see them everywhere i travel in the states. not sure how it is in the united kingdom but i was reading somewhere recently that they have juuls in the uk now or they're going to soon, something like that. if you can buy their kits online now where you live, i'd give it a try. been working really well for me. the only thing though: make sure you got it when you need it. always have it ready if you're trying to make that transition from smoking to vaping. SUPER IMPORTANT. otherwise you might just smoke a cig, which is what would happen to me during that rough transition period.
to make sure you always have it, i'd really suggest buying at least two kits so you have at least two batteries/vapes and can at the least rotate them on the charger. if you're out a lot, make sure you carry some kind of charger. car charger, portable battery pack, something. whatever works for you. just make sure you have what you need when you feel like you need it. and for that matter, find a pod flavor or flavors that work for you and get more than you need so you're not running out of juice and freaking out and smoking a cigarette instead lol. just my 2 cents. good luck!!!