Does the 'heat pex' sag as much as regular pex when the heated antifreeze is circulated through it?
I am doing a similar install in my bus this summer/fall and want to do it right the first time.
I'm pretty sure that is more flexable then regular pex and is more resistant to kinks too.
We usually use fasteners every 10" when not burrying it in concrete.
Oxygen barrier heat pex is made by a couple different mfg's and any would work just fine.