Magnesium bars are common for two reasons. First, I think the same armchair researcher who came up with the solar still got the military all excited over cheap, long lasting, small and lightwieght magnesiuum bars for survival kit. Of course, now we have SPARKLITES and poor Oak had to switch from beautifull brass units with replaceable flints to plastic- to save wieght and lower unit costs. The second reason Magnesium bars are so common is companies can sell a VERY inexpensive item for a rediculously expensive price.Do they work? Yes, if you practise all the information posted here. Are they worth it? That will be your final decision.