I ride 2-up ~90% of the time (and the gf is jealous of missing the remaining 10%.) My previous bike was a 1995 Yamaha Virago 1100, and I don't feel like I've lost any power by switching to the Wee - feels like I've gained some top end, actually, along with lots of smoothness.
Together, we tip the scales at ~450lbs., and often carry 50+ lbs of gear. With all that, and even in 6th gear, there's enough power at highway speeds that I don't usually shift into 5th until we're coming off at the exit. Well, once - but that took riding to the Catskills, finding a steep hill, and trying to pass a truck.
I've had lots of bikes in my life, but this is only the second one that's managed to impress me to this degree (the first was a French Honda CBF 750, back in the mid-1980s; it used to eat literbikes for lunch with boringly predictable regularity, and was a great, comfortable cruiser to boot.) I've already taken the Wee off-roading, climbing over boulders and through deep mud, and put a couple of thousand highway miles on it in the 6 weeks or so since I've bought it, and it is all around the most competent
bike I've ever had. Really a joy to ride.