It matters what type you get, apparently.
Spend some time reading on "vaping" websites to see what models people find worth the investment, because it really does seem to affect the likelihood of enjoyment and success in quitting. I am not a smoker, but I did a lot of reading when buying for someone else recently, and the person I bought for ended up being very pleased with the purchase and has cut down steadily over the past few months.
I bought the Joye 510, manual version with a PCC charging case, which seems to be a highly recommended model for light or moderate smokers who want something that looks like a real cigarette. From what I can tell, very heavy smokers are often advised toward bulkier models that allow a more intense input and longer use. A USB charger is also apparently a very popular accessory.
Also, check out different flavors. I was sure that the smoker I was buying for would want regular cig flavor, but after reading a lot of testimonials from ecig users, I threw in some unusual flavors,too. He was actually surprised to discover he prefers the vanilla. 
Good luck. I think a lot of people are finding ecigs very helpful.