I've seen these around. I imagine they have all the quirks and weirdness of any AZTech card, but they're not really bad. Compatibility on my AZT boards was always hit-or-miss, but certainly no worse than most other cards and they were generally passable. I have never owned this model personally, but I suspect getting that modem to work would probably be a pain in the ass.
Strangely, I just ran across my PCI one which has a weird radio tuner board connected. Wouldn't recommend that model, it's flat out weird and doesn't work well with anything beyond the Windows interface. The ISA ones are generally better.
Of course, you'll not beat a real Sound Blaster or one of the other brands that had proper support, but if you don't have those it is certainly a viable option.
Sucks that yours doesn't seem to be working. I wrote out the information primarily for future reference or for use by others running into this thread.