The Issue
Using Pitch 'n Time LE for Logic Pro, the Prelisten function in the Factory Time and Pitch Machine doesn't sound as good as Pitch 'n Time should.

Logic Pro doesn't currently support Prelisten using Pitch 'n Time LE, an internal algorithm is used instead. At this time it is unknown whether or when Apple might fix this.

Workaround
To hear the true sound of Pitch 'n Time LE when working with Logic Pro, Process the audio, have a listen and use the Undo function if you wish to make further adjustments.