Which pillow is better HARD or SOFT?

All of the pillows are specially designed to be used with FIR mats and for short procedures before sleeping (harder one) or as a separate pillow just for sleeping and relax ( softer ones ).

The pillows are supposed to be HARD to provide better head and neck position during FIR heat sessions on hot stone mats. They are not for comfort or lengthy procedures. 

Of course, everybody is different, and some customers may sleep on them starting the first day, but most use them occasionally for short-therapeutic procedures.

For longer sessions, sleeping, or relaxing, it may be better to choose the SOFT Pillow.

Or you may choose a SOFT memory foam gemstone pillow with GENTLE cervical support. 

Again, the softness is relative, as all pillows with crushed crystals are significantly harder than typical sleeping pillows made with natural or synthetic down or feather-like fillers. 

But if you need to make the pillow really soft, the best solution is to have the cover removed from the pillow insert (there is a zipper on the back) and put it on a standard pillow, or fill the case with shredded memory foam like the one used for expensive bean bags. 

You can also put your regular sleeping pillow inside the valuable pillowcase with crystals, or if it is too large, get the filler out of your sleeping pillow and load it inside the pillowcase with gems.

Other functional fillers are 3-D Air-Mesh Pad or Eggshell Pad materials. Both are ventilated, gain any shape, and are available on Amazon.

That would be best for a comfortable all-night sleep.