I'm not an Elvis fan, but, as is often the case, I was tempted by a cheap price and the promise of some - any - surround.
I think this disc is unfairly maligned. Forget tracks 19-31. They are mono with lots of reverb. I can appreciate why that upsets people, but if they weren't on the disc, maybe people would notice what it does have.
There are 18 tracks - 50 mins - of surround on here. The first 6 or so are proper surround. Maybe not brilliant, but alright. 7-18 are of varying quality. I think they are 4, 3 or even 2 track originals which have been mixed/ upmixed/ manipulated so that you get something in at least one rear speaker most of the time. These are recordings from the early 60s, what can you expect?*
If you like Elvis and the price is right, expect 20 mins of good stuff, 30 mins of acceptable bonus and pretend the next 30 mins don't exist. As I say, I am not an Elvis fan but I am a surround fan and I am not disappointed.
[*Of course, these days you can expect something more. Those simple but mono recordings are prime targets for demixing.]