Which of the following systems of FIR saunas do you believe is best? Are some gymicks or are they the real thing?

Hi everybody:

I am in the process of purchasing a FIR (Far-Infrared-Sauna) sauna for our home. We definetely want one but my head is like a football!Here are the options I have encountered:
1) zirconium ceramic tubes filled with quartz crystals,silica, minerals (only mentioned manganese) and oxides in the form of sand. Now, I know must types of sand have silica, quartz is a form of silica...These have an electrical resistance wire inside. There are 5 or 6 for each wood 2 people cabin.
2) Ceramic tube with an electrical wire, another ceramic tube hosting the inner one.
3) The carbon fiber heaters are a high density organic carbon fiber material, 2 layers sandwiching a quartz filament.There are 6 in a double unit.

One sells person says that the carbon fiber heaters are too high inside the cabin and it is bad to have them in front of the frontal lobe of the brain.

Others say that the zirconium ceramic with sand is a guimick, that it is an inneficient system...Of course those who sell them swear by them.

So,which is best and why?

As for the wood,is it true that fur or hemlock will crack very badly in the near future? Is it true that red western cedar is the best? Tweet