tKf,
Inside my helmet I have 10-80s. I bought two sets s/hand a few years ago for £4k because they came bundled with some other stuff that I wanted (an aeroplane share!).
I had always used my old trusty 10-30s until then.
I was suspicious as the 10-80s were almost exclusively plastic as opposed to the std DC s/steel headband.
Anyway - the 10-80s are better (sound/comfort/clarity) than the -30s but may not be as rugged. That said they are headsets not scrum caps.
Could be a very good £85 spent.
Any chance that you can have them on trial/approval for a short while before committing to the purchase?
I can make mine available to you for the 15th if that would help.
Stik