I used to use Daemon tools exclusively, but started having issues with it locking up my computer, so I switch to Power ISO. But now I keep Alcohol 120%, Daemon Tools, and Power ISO on my computer for mounting CD Images. I mostly use Power ISO but every now and then I come across one Power ISO wont mount (mostly BIN & CUE files). Then I resort to Alcohol, then if that doesn't work Daemon tools. Between the 3 of them I have got every good file to mount.
So there are several good alternatives out there if Daemon Tools wont play nice.