The re-release of Pet Sounds has both the mono and stereo versions but they didn't do that on the Beatles re-releases because it would 'confuse the public'. Sure it would. I think it's called gouging.
I think its important - I've often noticed with Beatles songs that if you've only go one speaker working (or one earphone in) you only get half the song! For example if your right speaker isn't working you may not get the words or melody of the song, only the drums and bass. Bit of a bummer if its a fault with the speakers you can't fix. That's were mono would be handy.
I listened to the samples of "Getting Better" on the website that was linked, and the stereo version definitely sounds more detailed, crisp, and three dimensional (if I may use that term for music) than the mono version.
The mono version sounded tighter and more compressed, like it's a recording from a radio speaker, but certainly more like how I expect the Beatles to sound.
If I were choosing which to purchase, I'd go for the stereo - it's the Beatles reinvented for the modern era.
Mono would be like listening to them all those years ago in your bedroom on the old record player, quite nostalgic, but stereo would be more like hearing them live (minus the screaming).
Which experience would you have chosen back then?
Sure it would. I think it's called gouging. 
