DC or Bose A20
It all depends how much you want to pay, my DC'shave been almost indistructable with the 10-40 surviving thirty years of GA flying, a lot of this was instructing so lots of unplugging and moving to another aircraft. The DC is still going strong but due to my work Sennheiser looking like it was about to fail ( the wire started to fall apart after ten years and about 7000 hours flying ) I have just got a Bose A20.
The Bose brings a new and very welcome silence to the 737 cockpit.
While I have not yet used the Bose in my light aircraft it will get approaching 900 hours use a year in the 737 and so to me is worth the (tax deductible ) expence, I would suspect that the very high quality Bose is a bit too expensive for all but the high use end of the GA market.
There is a company in the USA that has an after market kit to fit active noise suppression to DC headsets, this has got very good reviews in the press. It is my opinion that a DC with this anti noise kit fitted would be give the best value per hour flown for the average GA pilot.