I purchased my D1S new in 1991. I remember it selling for around $1400 back then. I have gone thru many receivers over the years, and the D1S is a keeper for me. I use it in my home theater setup, but 80% of the time, I use it in direct mode for two channel listening. It's a very clean sounding and powerful receiver, that has no problem with loads down to 2ohm. I've owned several other pioneer receivers over the years, including the SA9900, VSX7500, and one of my old favorites, the SX780(which is still working great in my father's workshop).
In addition to my D1S, I also own three Harmon Kardon receivers; an older 80's HK-590, a mid 90's HK-AVR40, and a new HK-3490. The HK's sound very good, the D1S sounds better.