I flew last week with my new 22 with the dual exhaust. I haven’t yet done a careful analysis but on one occasion at 6000 ft around 15C best power (monitor said 76%) resulted in TAS of 175. This is at max gross with lots of bugs on the airplane…reputed to be worth another 5 knots or so. It doesn’t at first glance appear to be faster than book. The new cowl has big flares for the two pipes - I wonder if it might be draggier than the old cowl.
I don’t have any basis for comparison on noise level…a couple of times I flew an hour or more before realizing I left my ANR switch off…quite reasonable noise level but certainly you want a headset.