I've heard a few of the high-end Sony ES SACD machines from the early 2000's, though not specifically the XA777 model (though I have heard the other higher-end 777 and owned the SCD-1). And I'd agree that the Redbook playback is uniformly mediocre, in fact below-average by today's standards. For example, I owned an SCD-1 that was easily beaten by my Meridian G08 (v1) in Redbook playback. And now I have an NAD M51 that I think is quite a bit better than what I remember getting from the G08.
But that's un-modded. Good modding can bring these back to relevance. And some of those Sony players certainly had great build quality. Another example: I have a Denon 3910 with Modwright Ultimate Truth mods. I used to own a stock 3910, and its Redbook quality was poor. The Modwright 3910, on the other hand, is very respectable; it can compete with the NAD M51, and adds a slightly sweeter sound to Redbook, though the M51 is a little more detailed. I prefer both of these to the Eximus DP-1 DAC on Redbook.
I also had a Sony ES 5-disc changer from the mid-1990's (un-modded), and that was actually more analog sounding than their higher-end 2000's models (i.e. I'd rather listen to Redbook on it vs. an unmodded SCD-1). It absolutely can't compete with the resolution of today's DACs, but it was an enjoyable listen on the cheap.
But that's un-modded. Good modding can bring these back to relevance. And some of those Sony players certainly had great build quality. Another example: I have a Denon 3910 with Modwright Ultimate Truth mods. I used to own a stock 3910, and its Redbook quality was poor. The Modwright 3910, on the other hand, is very respectable; it can compete with the NAD M51, and adds a slightly sweeter sound to Redbook, though the M51 is a little more detailed. I prefer both of these to the Eximus DP-1 DAC on Redbook.
I also had a Sony ES 5-disc changer from the mid-1990's (un-modded), and that was actually more analog sounding than their higher-end 2000's models (i.e. I'd rather listen to Redbook on it vs. an unmodded SCD-1). It absolutely can't compete with the resolution of today's DACs, but it was an enjoyable listen on the cheap.