Good call on the magnet check. It turns out that the wheels on the Tempo are steel and those on the WS are aluminum! I'm thinking I should just do the switch... Sunshine hubs don't seem to have a particularly bad rep from what I've read and they're spinning really nicely.

And for the 700's -- the previous owner adjusted the pads terribly, and now I took everything off to clean the frame. I won't know for sure until I put everything back on and adjust it properly, but I think it would work.