My use of N165 is limited to 338 win mag and 300 Win mag. Neither are guns I've had long term, not any past history to compare. All I can say is its slower and burns really clean which is something I never even think about or care about. But I did notice when I cleaned at teh range and after the range.
I did shoot a really good group or two in my 338 with H165. I have not shot overy a Chrono yet. Got better groups with N165 than I did with Ramshot Hunter in my 338.
With my 300 Win mag I was able to work up to Max based on Viht reloading app. which after looking at other data the Viht app is was way hotter. Primers looked about like a factory round, hot but still ok. I chose to back it down 3/4 grain to compensate for hotter weather on the next 20 I loaded last night.
With that said, I am going to load some H4821sc in my 300 Win mag, RL19/N204 etc. in my 300 win mag.
My gut tells me the N165 will do better with Heavier bullets in my 300 win mag. Only 180 grains I had were Barnes and didnt want to load Barnes. So shot 165 gr Interlock. I have some 180 grain Speer Boat Tails and some Grand Slams on order.
I like to work up loads and go to the range. My be simple fun, but its fun for me even after all these years. With work and other stuff don't get to go very often, but will when I retire after the first of the year.