In reality they are hard to handle and smoke and end up being wasteful
Therefore, if science-backed, they have the potential to emit significantly fewer and lower levels of harmful and potentially harmful constituents compared to cigarette smoke
Corey CG, Holder-Hayes E, Nguyen AB, Delnevo CD, Rostron BL, Bansal-Travers M, Kimmel HL, Koblitz A, Lambert E, Pearson JL, et al
When you stop smoking using an E-Cigarette, you are still giving your body nicotine and so nicotine withdrawal isn't an issue (unless you are using a zero nicotine e-liquid), but you are eliminating the intake of harmful chemicals found in tobacco - like heavy metals that the plant absorbs from the soil - as well as the harmful stuff made by burning tobacco - like carbon monoxide and tar
Each material has its unique advantage, so its entirely up to you which one you want to go for