Well, my new Polar S410 heart rate monitor seems to work: I wore it for the first time at the gym last night when I did my combination of interval training on the recumbent bicycles and 15 minutes of elliptical training. On the right you can see my resulting pulse rates, edited slightly to remove the several data dropouts that occurred.
During the elliptical portion (the last third or so) I was probably pushing too hard. My max pulse rate should be around 174, and I hit a max of 167. I'll have to cut it back a bit.
It's a cute gadget, but I'm not overly fond of the software, which doesn't seem to guide you into designing an appropriate exercise regimen. I'm working on some software to decode the information transferred via SonicLink, their sound based transfer system. I'll let you know how that goes.