RE: Which is quieter? Slimline or Bisson?
I have a Slimline Pitts on my Irvine 53. It's out of hand loud. Not sure if a Bisson would be quiter but the Slimline is certainly not.
I have a Bisson on my Moki 1.80 and it's a very tolerable volume. Nobody has ever said it was loud and our field is one that manages db levels very closely.