I smoke because I enjoy it and if I did go over to vaping the same rules would apply. I am considering it, but only because the real thing is getting so damned expensive. Can any vapers tell me if it gives the same satisfaction? I tried when they first came out and they were a poor substitute.
I think it depends on what you are using. The ones that look like fags are almost universally agreed to be a waste of time and money.
Starter kits usually consist of what is known as a CE4 and an Ego battery, which is basic but functional and it was enough to get me of the fags. I think the kit cost about £25 from a stall in a shopping centre and came with a 30ml bottle of 24mg liquid. I would however recommend paying a little bit extra to at least an Ego twist battery which allows variable voltage so you can tweak the hit a little and some of the more modern clearomisers (or whatever they're called) such as the Protank Mini 3 which I now use or the various variations of the Aspire BDC have good reviews too. There is new and better stuff coming on to the market all the time so just read some reviews before buying anything. The Ego twist batteries will work fine but I now have an iStick 30 which is slightly bigger and heavier but has much longer battery life, charges faster and gives much more control.
Just call at one of the shops or shopping centre stalls that seem to have sprung up everywhere overnight and ask to sample some gear. They will all probably offer the CE-4 and Ego starter kit. It does work fine but the trouble with the CE-4 is it tends to leak and it is a throwaway item whereas things like the Protank 3 have replaceable coils which works out a lot cheaper in the long term. But trying one of those kits will at least let you know if it might be of benefit to you.
When I smoked, I was certainly no athlete but would have considered myself reasonably fit and had no obvious breathing problems. On hindsight I was a gasping wheezing wreck, I just thought that was normal and feel so much better now it's unbelieveable.
EDIT: It will never feel quite the same as smoking, it will relieve the craving for nicotine but there are many other addictive chemicals in fags too but for me at least it ticked the right boxes by relieving the nicotine craving, giving me something to do with my hands and giving the sensation of smoking. You will also feel worse for a few days while your lungs clear but after that you are on the crest of a wave.