The best places to buy the hottest pepper in the world are reputable growers. Professional pepper seed growers isolate their plants either by growing them in a greenhouse or growing them far apart, sometimes at different locations. Peppers will readily interbreed with other families of peppers and
will not come true for saving seeds. The resulting peppers will not have the promised heat level, and sometimes will not even look like the variety promised. Small companies, especially on the internet, usually state how they keep their seed strains pure. Organic seeds are better than conventionally grown seeds since the plants had a full range of minerals and soil nutrients to better form seeds. DavesGarden.com is a good resource to find out the reputation of a grower, but some smaller growers are not listed there.