I just want to thank the people who commented in this forum about the Lightspeed headsets. I was quick enough to jump in and order one of the reconditioned 20K headsets that Lightspeed recently sold off (at about $200 less than a new 20XL). I’ve flown twice with it now and I’m impressed.
The first flight was a bit of “a new toy - what does it do” but on the second flight today I pretty much forgot about it, until half way through the flight I tried turning off the noise cancelling - it is amazing how much rumble it cuts out. I found ATC much easier to hear with it turned on - I suspect I have the radio volume quite a bit lower than I did with my DC headset. In-cockpit communications were also much easier.
So, thanks again. My partners and I have agreed in priniciple to buy 3 good passenger headsets for the SR20, and I think they will be Lightspeed!