Are Japanese Shiki-futons comfortable? Hello! I've been wanting to return with a Shiki-futon for a long time!...

Hello!
I've been wanting to return with a Shiki-futon for a long time! They save a great deal of space! But I haven't ever tried sleeping on one. Does anybody have one? Are they nice? Do you find it alright to only just use it on the floor or do you need extra things underneath?
Thank you for any aid! :D
Can Sunflower Oil be used for like things...
Answers:    The wooden frame for a futon was developed after the 2nd World War as the occupy American forces wanted to bring them home as souvenirs, but didn't want to sleep on the floor like the Japanese did. I would voice, as I have one as an 'occasional bed' that it's fine to sleep on the floor, and no, you shouldn't entail anything extra if your floor isn't too cold.