Interstate driving 55 to 64 with toad (JK jeep) and 65 - 70 without which is not often. Highways (cross traffic) five mph less than these speeds minimum. Wind changes everything but driving out west in winter you are going to get bad winds so practice makes perfect. Passed a DP in the San Gorgonio pass I10 (Banning CA) I was doing 45 to 50 and he was all over the road at anything above 40. Bad windy gusting day. The gust felt like I was on two wheels when they hit after being blocked by overpass. Felt good about the Safe-t-pass that day. Any idiot can drive too fast in good conditions. Sadly I have also tested my Axis brakes on a number of occasions without and with toad (Patriot braking system) they worked as we are still here and no accidents.
Noise levels in my unit are dependent on transmission gear (down shifting) more than speeds over 70. A few times to pass I hit 80. I pass at full power on two lane roads.
Also my Axis seems to love 64 mph at ~2100 rpms.