I recall that in the '80's, the Essential set was considered a rare item and commanded some premium prices before many of those songs found their way onto cd. While the packaging and the contents are very special, the sound quality of many of the songs is not what is available now. In fact, I recall one review of the album that said some of the songs sounded as though they'd been recorded through a wad of Kleenex.
The Frank Sinatra in Hollywood album, on the other hand, was my first experience at hearing the early Sinatra with true clarity. Someone paid attention to more than the packaging on this one. Once I get a cartridge for the old turntable, I'll see if I still feel that strongly about this set.
As far as the fake stereo on some of these '60's releases, Columbia's version was (thankfully) pretty mild compared to the echo chamber effect you get on the Capitol versions.