I heard the Rhea in a shootout with several other phonostage and neither of us was impressed - we pretty much unanimously felt it was very disappointing. It was slightly noisy too.
Some short comments:
- Sutherland Ph.D. (nice balance, good flow, quiet)
- McIntosh C1000 pre (excellent flow, not the best resolution)
- Canofer S (best overall balanced and very good soundstage resolution)
- Vacuumstate JLTI (finely detailed, very wide soundstage and excellent separation between instruments, lean)
- Rhea (slightly noisy, average soundstage resolution, forward upper midrange, loose bass)
Some more phonostages I have more experience with:
- Pass XOno (excellent resolution, best bass and extension, dynamic, slightly mechanical and not the most saturated tonal colors
- Wright WPP200C (good balance, average resolution)
- Trichord Dino (dry, good resolution)
Most of the above comparisons were done using the following combinations:
- Verdier, Da Vinci, ZYX Universe
- DPS 2, Schroeder No.2 Allaerts, Lyra Argo
- Scoutmaster, JMW9 Plus, Dynavector XX-2
Of course mostly my personal impression and YMMV.