Triple that (but I'm at 4). The only time I have leaking is when I rebuild my own coil, and honestly each time I know exactly what
I did wrong (not enough cotton, letting the wick get old, or overfilling). Well that and when I left a near full tank in one of them for over a month without vaping it at all.
As for recommendations for your father, I think his smoking habits will surely come into play. I know a couple smokers who have hated vapes because they "are too harsh on their lungs" which I'm sure we can all laugh at, but we all know it's a much different hit than a cigarette. It takes some getting used to. But, knowing plenty of smokers I know some that direct lung hit unfiltered camels, I know some that MTL lights. There's a wide variety.
I've always said that a smoker has to want to quit smoking otherwise it's not going to happen. But, if they do, set them up with a simple setup, what you have is actually more advanced than I'd suggest, but it's solid. If he's concerned about leaking, let him know that if he can deal with that for now that there are plenty of options that remove that issue, but he needs to deal with that for now, get through a few weeks and he can upgrade. If he is refusing because of leaking, well he's just making an excuse, something every smoker does to not quit.
I'd get him an eGo-T (or two due to battery constraints) and a tank to go with it (I'd suggest the Kanger EVOD or something cheap), really no reason to drop a ton of money on something that he may just brush off because he has no desire to quit.
That said, remind him. This stuff actually smells good, after 2 weeks or so of coughing up crap the issues with his lungs will go away (unless it's more serious), it's in general much cheaper and can be made even more so with a little work (yay hobbies!), it can taste great, and did I mention it doesn't smell like shit?
Depending on his smoking style, even a basic setup should be a great start. If he wants more then let him know there's a HUGE variety beyond that, from stuff that you just slap together easily to stuff that becomes a nice hobby and saves you money. The basic should be a nice start though if he actually wants to stop, this is great because you not only get the nicotine still, which curbs the physical addiction. But, IMO the mental addiction to smoking is as strong if not stronger, and vaping satiates that just fine. Again, let him know that the first couple weeks will still be tough because his lungs will be expelling all the tar filled crap in his lungs, but if he can get through that, he will likely find it very enjoyable and should feel much better afterwards (be able to actually breath and things will have a more distinct smell and therefor taste).
For myself... well I'm a bit out of the norm, I didn't smoke strait cigarettes... However my brother has now more or less quit smoking. I say more or less in that he'll still indulge at a party and socially, but down from a pack or two a day to a pack or two a month (depends on how often the guys and us get together and drink).
To end, listen to these other comments, I know I've heard quite a few issues with leaking on the Kanger tanks, I know my brother has those issues with his (I'm still debating on giving him my old Atlantis, I still love that little thing) but I've never checked out his tank fully to make sure all the O-rings are solid and everything is clean, so user error could very well be the issue. Anyways though, Good luck. I know my brother feels much better having quit smoking, I know I feel better having quit my habits, clean lungs are nice.
