MIDI sounds can be fabulous, as good or better than "actual" for some instruments (especially bass, piano, drums). Particularly if you're recording your own tunes, able to play the parts on keyboards, yes, choose MIDI instruments, and you'll get great results. No hassles about setting up mics to record the instruments etc.
But if we're talking about Band-in-a-Box ** styles **, its a different question....
Band-in-a-Box RealTracks styles aren't just real instrument samples, that could be duplicated with a good MIDI modules. They also contain the nuances of a real musician playing his instrument. Band-in-a-Box MIDI styles do not.
Rather than try to describe which approach is better, why not have a listen to the results, and judge for yourself.
Comparison Demos... Band-in-a-Box RealTracks styles and MIDI styles
http://www.pgmusic.com/forums/showflat.p...SID=#Post347191