Although I have not heard the Athena AS-B1.2, I did have a pair of the AS-B1. I found them honky, nasal and hollow sounding, as if they were missing a large chunk of midrange.
When directly compared to my two other pair of inexpensive speakers, the B&W DM302 and the KEF Cresta 1, it was very obvious how lacking the sound was. The AS-B1.2 would have to be substantially different.
I sold the Athenas for $50. I just wanted them out of the house.
I am curious about the AV123 x-ls, but no one has heard them yet, as they won't be available until sometime in March. I see that Danny Richie of GR-Research designed them, and I own a pair of his higher-end Diluceo monitors. Note that they do not have grilles and are unshielded, if that's a concern.
Hopefully someone who owns the Energy Connoisseur C-3 will chime in.
After my experience with the Athenas, I will probably never buy a speaker from the Energy/Athena/Mirage consortium, although the Energy may very well be a fine sounding speaker. There are just too many other fish in the sea.
Good luck in your search, I'm sure you'll get a bunch of good recommendations on this still young thread!