I know this is a tricky topic. If ecigs had been around when i was 16 and started smoking, i probably would have tried them also. It wasn't so much the smoking and nicotine at that age, it was the simple fact that I was doing something that I knew I shouldn't be doing. If ecigs were around and I would have had to be 18 to buy them, i would have found someone to buy the stuff for me. With that being said, he needs to want to quit smoking, if not he is going to continue doing it behind your back. You could just get him a cheap starter kit, give it to him, and see how he does with it. Vaping is leaps and bounds better for him than smoking, as you already know. The biggest thing for me to switch was a good tobacco flavor,so try something like that. The only way you are going to get him to switch is to just be supportive. Allow him to vape around you! It doesn't sound like he is smoking around you.