There is another option, Paul.
When I was looking around, I found Clark Rubber had some great looking foam mat/tiles without the holes. From memory they were bigger (say 1m x 1m) but the price put me off
. I had the camping mats with the holes in it anyway and decided to try them first, and I really like them
. They work well in my obs!
With a bit of luck, if you look around a bit you'll find some without the holes if that would be preferable and avoid the carpet perhaps
... but then I suppose the floor won't breathe...
... just a thought.
Al.