what got me to using EAC with a cue sheet was CD-Text, but I quickly discovered that track to track synchronization was a side benefit.
My personal favorite example of "Gapless playback" is on the first Boston Album between track #2 "Foreplay" and Track #3 "Longtime"
where the long instrumental ends on a long sustain organ note on which the next track builds.
Until I had EAC it was flat impossible to get that to play gaplessly on a duplicated CD without a distinct "pop".
IT drove me absolutely nuts, I must have wasted 20 CD-R's
(fortunatly cheap-ass Ritek discs) trying to get it right
First time I tried it with EAC it went PERFECTLY.
SOME audio extraction software automatically appends silence at each end of an extracted track at the time you rip the music
if it is doing this you can spend time fiddling with a wav editor to eliminate the silence OR you can take the original source and rip it again with software that doesn't screw you up from the first step...
FWIW I have yet to achieve gapless mp3 playback even with LAMe compressed 320K mp3's, but that's probably more a matter of the ancient playback equipment I'm using.