Tsk, Tsk, Tsk... The uninformed speak (;
CUE/MP3 is a kind of "dirty workaround" to get small sized disc images. It was common for pirated CD-based console games (for example PC-Engine, Mega CD) some time ago.
The big problem with MP3's is that they are not exactly the same lenght as the original WAV's, no matter how they are encoded. There is _no way_ to create a CD with original timings out of ISO (BIN)/MP3 files, because the timings of the WAV's decoded from MP3 will be different than the timings of the original WAV files. In most cases, you probably won't notice the difference in lenght, though (maybe silence before looping a track, or audible pops at the beginning/end of a track, or something similar).
There is currently no program that can mount ISO (BIN)/MP3. Some console emulators do support the combination, though - but even with these emulators, there'll be some serious audio problems when playing the game.
Bottom line: don't use ISO (BIN)/MP3 (or OGG). It's crap. Dump your originals as BIN/CUE, and everything will work fine.