Ah, you are going with "best of both worlds" biamp approach, just like me.
Coincidentally, I'm using my VAC 30 watt (like 845G) tube amp for top (140 Hz) and SS amp below that. I use an active x-over, though.
It also so happens my speakers are rated at 95dB sensitive as opposed to 94dB for RMX Neo panels.
166 Hz is probably low enough to avoid a lot of problems matching top and bottom amps' sound character, but I still expect you will spend some weeks finding the right combo of interconnects, power cords, speaker cables, footers to blend the two amps's sound character. Been there, done that, got electrocuted, etc...
So when can we come listen to your setup? Where in OC are you?