I've always used regulated mods with external batteries. Never owned a built in battery. Didn't start with kit(s). I've only bought 1 kit, after I had already been using sub-ohm and it came with a regulated mod.
Even tho the price of some kits may be appealing, imo quitting smoking requires more than throwing a little change at it. Something that has AF(air flow) adjustments and power (wattage) adjustment, and uses juice you can buy in a bottle so you can choose your ratios, means you have many different vape producing options all in one setup.
ie, you buy a $20 kit and it doesn't work for you/you don't like it, so you get what seems better, say a $40 one and that one doesn't cut it either. There's nothing you can do about non ajdustable starter kits and you just spent enough on those 2, to get one that can mimic what those 2 kits did - plus more, because you have control of adjustments. And, your not strapped to buying from limited juice selections, pods, or proprietary what-nots to keep it going, which is expensive.
Because it mimics a cig, my first 8 months was MTL Nautilus tank w/ single 18650 regulated mod @ about 12w.
I currently use rebuildables. It's been a while, but Nautilus is still great to start out with. I first sampled flavors for one that I liked. I think FDA (if in US) doesn't allow free sampling any more, but don't quote me. I'ts at least very cheap, as in change, to sample if you find the right b&m. I also started with the equivelent of nic that my cigs had, and moved down.
The tank, or vape delivery(business end I'll call it), is of the upmost importance. Getting power to is is easy.
As you can see, my opinion is to not first shop kits - which leaves all other products out of the stop smoking equation. Buying mod and tank separately also means you can just change tanks for a different experience if/when you want.