I've been using both a 28X and 29QW for some months now, to hookup a Palm, old GlobalVillage modem and the IBVA personal brainwave device for which I'm developing software.

I've not had any problems since upgrading OS/X to 10.2.5 - prior to that I had the Palm drop out on HotSync a few times.

The Keyspan hardware and software basically just works for me and I'm pushing it pretty hard.

My main annoyance is that every time I replug the device I get a different device name.

That's not a problem for my software but the modem connection menu remembers all the old ones - I have a list of useless USA28X1P2 and similar names. I assume that is an Apple bug.

I have a now-useless SerialBee for which OSX drivers were never released. Although Keyspan's hardware isn't cheap, I have to give them value points for continuing to stay in business with this device!