Sony SACD 1 or 777

Anyone out there know the difference between the two if any? And what are listening impressions between CD and SACD.
...Haven't heard SACD but have heard CD upsampled to 192 kHz and, let me tell you, it was THE most natural, believable, wholistic, just plain wonderful thing I've heard to date. System: dcs converter (Elgar?), dcs upsampler, Thiel 7.? (flagship) speakers, Goldmund monoblock amps. Put PS audio Power Plants in front of it and I might not come back...
Scotty: Three features separate the SCD-1 from the SCD-777ES. SCD-1 has balanced and unbalanced analogue outputs. SCD-777ES only has unbalanced output. SCD-1's power transformers are "encapsulated". SCD-1 has five carbon steel isolation feet whereas SCD-777ES has four feet of an unspecified material. Otherwise, they are electronically and mechanically identical. (Of course, they are different in color.) I own the SCD-777ES and use it primarily as a transport into a Levinson 360S. Both the SCD-1 and SCD-777ES are very good CD players in their own right. You definitely can hear the difference between SACD and 16/44.1 if you play a disk that allows you to switch between the formats. The problem with SACD presently is the lack of sufficient softwares. I am a classical music fan. There aren't many classical selections on SACD now. Furthermore, almost all the classical SACDs currently available are formatted from mediocre masters. My limited experience points toward better-recorded 16/44.1 thru' an excellent DAC until more SACD selections are available. To sum it up, SACD is the better format but we have not been fully benefited from its current application. Thanks.
As an ex-SACD1 user and I now own a 777 machine. So naturally, I prefer the 777 over the SCD1. The main reason, I like the sound of the 777 via single/ended output which is somewhat sweeter and more easy to take at the midrange/vocals than its big brother. Not to mention you save at least a grand, enough to start collecting your new SACD disc collection.