Nobody answered!
So, I thought I'd come back and report on my experience so far in case someone ever searches for "wrist weights" here.
Well... I walked with them for the first time today. It was my light walking day, not as long as usual and no hills, so I thought I'd wear them for the first mile and then throw them in the car for the rest of my walk, but they were pretty comfortable and I thought I could handle it, so I wore them for the whole, I think, 2.6 miles. I did feel it during the walk, but it wasn't hard. I did focus on my posture the whole time, though. I think it's good that I had already been working on my walking posture.
I'll try to remember to come back and update about how its going after a few weeks.