To allow smooth pitch glides over a large range, most of these midi transcriptions have the pitch bend range set to two octaves. The standard pitch bend range is a whole tone. Your midi player needs to be able to play clips with a two octave pitch bend range to hear it as intended. Most can.
If the transcription sounds similar in general shape to the original but varies in pitch far less than expected - you may have a midi synth that can only play the standard pitch bend range - or even one that is unable to play pitch bends at all though that is rare. Try them with another synth - Quicktime, for instance, has its own inbuilt midi synth and plays them fine.