When I bought the Sgt Pepper album on its release, I looked to save a dollar and bought the mono vinyl album. In those days, stereo albums were priced ~ one dollar more than the mono version. I was disappointed when I heard the stereo album, both in vinyl and CD. Until the release of the Mono Set recently, I never bothered playing my stereo CD which I bought in 1987. To really hear Sgt Pepper, I would take out my vinyl album and fire up the old turntable.
The mono remastered CD closely emulates the mono vinyl Sgt Pepper album.
Try checking out the remastered stereo and mono versions of Lucy In The Sky With Diamonds on YouTube, lunchpunch. The mono version is not sped up as is the stereo version. It's fuller and more ethereal.