I really like the SCD-1, it just sounds great. I compared to the 777ES before buying, and I did not hear that much of a difference. I was going to buy the 777, but they made me a deal on the SCD-1 I could not refuse.
I have since heard the Marantz (At a dealer) on a 380S, 33H and Vienna Acoustics Mahler... It sounded simply Awesome! Had the dealer plug the SCD-1 in and... It sounded as awesome to me. I was not able to hear much of a difference between the Marantz and the Sony, although the Marantz seemed to produce a touch less hiss. (The only way I hear hiss on the Sony is at full gain with my ear to the tweeter)
The super Audio CD format is just great. I just want there to be a lot more music. Many of the recordings are re-masters, and you can very much hear the limitations of the original recordings on most of those. I have a few SACD that were recorded on DSD equipment, and boy... They sound awesome! One of the demo discs that comes with the machine is a dual layer disc, allowing you to hear the difference between SACD and CD. Not surprising, SACD is much more detailed.
The irony here is of course that I know I bought another Betamax... DVD-A will eventually win the format war, and the SACD catalog will probably never grow past 600 titles. Even so, I enjoy the fire out of SACD. If you have the money to burn, and you want the most awesome CD sound ever, the SCD-1 is worth the money.
Niels.