Such mats are good in cooler weather and more comfortable than the ventist, which really has very little "give". Bony areas do not compress the ventist pad and these become pressure points but in hot weather, the cooling effect is a winner on the ventist

I have used a yoga mat and an ultralight backpacking pad cut to size. Something like this one.

https://mountainlaureldesigns.com/product/1-4-foam-pad/