Update. After a few days of letting the speaker play on repeat they are loosening up. They are still not 100% (probably have about 40 hours on them now) but are getting there, enough so I can now begin to use them to judge the electronics driving them.
To date, the chain feeding them has been: Tidal Hifi -> Chromecast Audio -> Chord Mojo via optical (Chromecast direct during the day when I am just running speakers in) -> RWA Signature 16 -> Omega Super 3HO Monitors. Cables are nothing to speak of, set up is basic at the moment, subwoofers are off, and the room is untreated.
In my 15' x 22' x 13" (vaulted ceiling) room they play plenty loud using both the RWA and my Fi-design (Oliver Sayes-built) 4wpc 421A amp. Two points thus far:
1. In this room, these speakers do not have enough bass to provide the visceral impact I prefer. However, they do have enough bass for most people, and likely put out more bass than small "subwoofers" common in inexpensive HT systems. I haven't tried these in my smaller room, but in this larger volume space there are only so many miracles a 4" driver can do.
2. While the speakers are nominally 97.5dB, the RWA sounded noticably better than the SET 421A amp. It had perceptibly more drive and may have sounded a little cleaner. Both amps are dead quiet (RWA is battery powered, and the 421A is a pi-filtered IDHT). However, the 421A had better bass than the RWA. The 421A may be able to deliver more balance power into the rising bass impedance of the speakers. The RWA doubles in power into 4 ohms, so it may be delivering more power (up to 32wpc) into the upper bass and midrange than it is into the deep bass. If the impedance rises to 12 ohms in the bass, the amp would only be putting out about 10wpc. Conversely, the 421A is running the 8-ohm taps off its Hashimoto OPT's and may be delivering more bass into the rising LF impedance.
I want to get to about 100 hours or more before I try to start integrating the Rythmik subwoofers. The RWA has a separate set of preamp outputs, so I can run the Omega's full-range off the built-in SS amp and adjust the crossover controls of the Rythmik's. Both speakers are fed from the tube stage of the RWA.