Sorry, there are no good, free splitters on the Mac.
Fission is the best though, hands down. I use it all the time.
The only other one worth looking at is
MP3 Trimmer. I prefer Fission though because it's easier to use and it also supports AAC files. The only time I use MP3 Trimmer is when I have to cut up an MP2 file, because Fission doesn't have MP2 support.
Edit: Looks like there's been some development on the freeware front since the last time I checked. I can't vouch for their ease-of-use or support for CUE sheets, but here are some you can try:
Macsome Audio Splitter:
http://www.macsome.com/audio-splitter-mac/
AudioSlicer:
http://audioslicer.sourceforge.net/
cue-splitter:
http://www.macupdate.com/info.php/id/13093