I doubt the skin will come into contact with the tubes mate.
though i do see your concern due to the front and rear being exposed.
that structure looks like its made from steel, so you should get a good fixing to that with your c-bar or whatever extrusion you use.
just make sure you fit it snug and i recon it will be fine as its not that big.
this is a good alternative to an acrylic panel and as you said, much more cost effective if being changed periodically. its also cost effective when you consider acrylic can easily be smashed. skins do still tear or get slashed, but your outlay replacing will be buttons in comparison.
i wouldnt say its a long term solution, but if your customer is trying to cut you down on the promise of more regular work from the same job, then explain to him you have this alternative based on what he is promising to do. if he keeps your word you will have a fresh taught skin each time and if the plastic tension straps are getting brittle, they too are cheap replaced.
this is system is very much the same as the spirit flex one.
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wpuld be interested to hear how you get on with it.