The cheaper one doesn't work, but the one labeled 125 HSM does work and is recognised as an Apple card, despite the documentation not mentioning Apple at all. I should mention that because there are no special drivers for it, it won't work in 125 Mbps mode but 54 Mbps isn't so bad compared to being tied down to an Ethernet cable.
I'm currently using one as a software basestation in my PowerMac dual G4/800 so my PowerBook can be anywhere in the house. I've got another one for the PowerMac G3/800.
By the way, since they're clearing out the HSM stock for the Pre-N/eventual 802.11n products, they've had really good pricing on the HSM cards. I got one for $40.