I briefly had the RB1070 in my system and could not wait to get rid of it. I dislike that sterile, lifeless sound. It had no "balls" whatsoever. I went a week or two without turning on my system. Hated it. I used it to temporarily replace another older amp that started acting up, and got it as a hand-me-down so fortunately, no money lost.
The Nak PA-5 was originally a Nelson Pass Stasis design (same as the Threshold S-series power amps). Properly maintained (it would need a cap upgrade by now), it would be a good bet. The "II" version is still basically the same but has had a couple of minor modifications done by Nakamichi. The PA-7 is even nicer but you're looking at $750 or more for a clean example. It runs on the warm side, but easily drove any speaker I threw at it.
The Nak PA-5 was originally a Nelson Pass Stasis design (same as the Threshold S-series power amps). Properly maintained (it would need a cap upgrade by now), it would be a good bet. The "II" version is still basically the same but has had a couple of minor modifications done by Nakamichi. The PA-7 is even nicer but you're looking at $750 or more for a clean example. It runs on the warm side, but easily drove any speaker I threw at it.