I went with S1 because (1) I could try the full version out in advance and (2) it pegged out each of my priorities: Mackie implementation, Melodyne integration and ease of comping. Comping took a bit of fiddling, but I'm faster in S1 now than I was in SPlat, after just 4 songs. (And I STILL *LOVE* SPlat!)
That being said, my needs are kind of modest, and I know that other types of users will have more elaborate needs. But I NEVER use loops or included plugins, and seldom use MIDI (though I can, when needed).
BTW, my first Cakewalk software came on 5-1/4" floppy disks, so I'm not new at this...
But I CAN learn a new app or two. :)
S1 is fine for me. Your needs may be very different...