I have been fortunate this December to log 30+ flights on one of the first regular production run DZ 170's. My Comp-ARF Integral which has about 90 flights logged with a DZ 160 is the airframe I am using for evaluation and break-in for the 170. Being familiar with the performance of this aircraft with the 160 I can truly detect the added power/torque advantages of the 170 especially since I am using the same prop/fuel/plug/throttle curve configuration.
The significant difference is the middle power-band torque. Between 1/3 to 2/3 throttle I detect more power/torque authority. There is a reduction in the need to make throttle adjustments to maintain ideal cruise speed. In addition the transition to vertical from horizontal cruise is cleaner, not as much P-factor, I assume this is due to not having to go to a higher throttle setting to carve the desired radius. I am now throttling up after completing the radius instead of before or during.
In summary the break-in, and initial runs were easy and straight forward. One notable though is the increased compression over the 160, make sure you get a good prime and have a fully charged capable starter. This is one stout puppy. The idle and mid-range appear to run smoother (less vibration) and the transition from low to high throttle is outstanding.
APC 15x11 4-blade
CoolPower 30% heli