If you are like myself and love to burn incense,  the best ones to purchase are the ones that are charcoal based which makes it a very efficient agent  for the absorption of essential oils in the making of top quality incense sticks. Charcoal based incense produce a much safer environmental atmosphere as well as a powerful yet non overwhelming fragrance that lingers for hours. Other based type incense from my experience smell of wood when burning and use alcohol when processing which explains why some incense do not stay lite once the incense have become old and dryed out.  In my opinion hand dipped incense that are not charcoal based and use alcohol base fragrances, are not as good of quality as those incense that are charcoal based that use pure fragrance oil during the manufacturing process.