They definitely work. I've been using an E220 pretty regularly on my Mini 9 for most of this year. I'd been using it prior to that on my iBook and just copied across the driver installer and followed the instructions. I was then up and running. Note that I am not using any sort of application though ... I followed instructions to set it up in the Network Preferences and start it using the modem menu icon. The application for my modem was Windows only. So I can surf the net with it, but can't send or receive SMS, for example.
Don't have any specifics on the E169 though, sorry.