Yeah back at my old gym I used to stack three of their cheap flimsy ones to protect my spine and knees from the hardwood floor. I was hoping there would be a $15-$20 option that is thick enough for that kind of thing. I'm reading more of the reviews for this $20 one https://www.amazon.com/BalanceFrom-Purpose-Anti-Tear-Exercise-Carrying/dp/B00FO9ZRYG/ref=cm_cr_arp_d_product_top?ie=UTF8 and it sounds like it's too thick for real yoga cause it won't hold you steady but it'd be good for doing exercises like situps on hard floors. But then there are all those 1 star reviews saying it rips really fast...
Didn't think this would be so complicated =(