Hmm, I took the wife and kid in a loaded-to-almost-gross 172M to HAF for the first flight. Conditions were great at departure, though the aircraft climbed a bit, umm, lethargically. It got over the pass fine.
But it was a mixing bowl in the pattern over HAF. No one threw up, but the family insisted on a break at the 3-0 Cafe after just a 20 minute flight. Wind was fairly steady on the ground, but in the opposite direction as aloft. And I thumped the landing in a bit since HAF has a much wider runway than I had trained on.
We had a much better flight a few weeks later up to Pt. Reyes and Petaluma, in a 172N with a 180 HP conversion (not loaded anywhere near max gross). They wanted a break there, too, but that was after more than an hour and they wanted to watch the ultralights and get a snack at the 29er Diner.
I took my dad from Livermore to Hollister a few months later after picking up the same 172M from its 100-hour and doing the obligatory once-around-the-pattern. Of course I pointed out the cumulus forming over the ridgetops and explained it meant bumpy air. It wasn't that bad, but definitely noticeable, and Dad didn't complain at all. Landing was pretty good, but I had to dodge some idiot in a Pitts doing aerobatics in the middle of the SJC approach corridor (outside Class C, so it's legal, but stupid) on the way back. Mom hasn't been in the aircraft with me yet -- I think access is going to be an issue.