Thank you everyone for the nice comments. The system is extremely enjoyable. For me, the #1 sign that things are working well, and synergy is on point, is never wanting to leave the room or stop listening.
I give the KEFs a slight edge in imaging. They disappear just a bit better than the Spendors. However, the Spendors (for obvious reasons) have better all-around low frequency performance. They also have a more natural/fuller midrange presence that I adore.
I could live with either pair of speakers though, and that's exactly what I plan on doing!