as part of my prep for my complete renovation of my CT 13, i found an industrial flooring company that specializes in all kinds of flooring applications for everything from gyms to kitchens and playrooms to laboratories. there are similar materials you can get at Harbor Freight or Costco - but i dont think they will endure the heavy usage we intend.
a lot of it can be purchased by the roll/per foot (at typically 48" widths). and you can even choose between 3 or 6 mm. i have seen this stuff in fitness centers everywhere and since my wife and i are into diving and surfing and mountain biking ... i like the idea of a durable but still soft(er) floor surface. cutting it to one large piece means we can take the whole thing out to wash down after a big trip - and after seeing what was under the old carpet mine had, this gives me peace of mind. going for the thinner version will help me keep the weight
of the flooring to a minimum while still having a highly functional floor. i will likely also use it for the overhead strip too, for aesthetics (i like the space station look!). i am going with the 'coin-grip' texture that i see so often. not sure if this is useful for you but i thought i'd chime in.
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whats nice is they will send you samples of whichever styles you are interested in so you can see and feel the real deal before you commit to anything.