Thank you for your enquiry. The fillings you refer to will provide a soft feel in any mattress.
If you are going to use a futon style base, we would recommend placing some form of barrier, usually thin (3-5mm) MDF sheeting on the futon base before setting it up as a bed. This will provide the mattress with a uniform surface upon which to sit and prevent ridging occurring as a result of the mattress dipping into the gaps in the futon slats.
We trust that this if of assistance to you, but if your require any further advice or guidance, please call our office on 0161 437 4419.