green mountains

I had the Europa speaker and was very impressed.
I say give the owner Roy a call, he is most gracious with his time and knowledge.

how did they compare with the timepiece monitors?

I don't know how else to say this ,but the Minis absolutely blew the Europa away in every regard. You may want to look at Aether Audio's Spirit 1. (recommended an amp with 200 watts with the Mini)
I sold these after 3 fantastic years. I could have lived forever with the Minis, but I wanted to try a new slightly smaller stand mount.
I am waiting to receive the Vapor Audio Breeze which I plan to pick up at Akfest in April. The Breeze lists at only $1250 in standard finish. Ryan custom builds each speaker, so I chose a custom redwood burl,curved cabinet,with matching stands. Vapor uses the outstanding Raal tweeter and a very well regarded woofer in the Wavcor.
There is a very nice pair of Volents vl2 used here, for an amazing price. I have always coveted this speaker. Read the 6moons review. I would look real hard at this monitor. They are efficient, gorgeous , amazing bass, ribbon tweeter etc...
You may want to widen your search as there are many great monitors out there, and it may be fun to try different manufacturer.Please note, I'm not saying the Rio and Eos are not fantastic speakers. In you price range I would also have a look at Fritz carbon 7 or 5, and Selah Audio.
Good luck in your search.

First of all what kind of music do you listen to?

And can you describe in more detail the experience you had with the Europas and the Eos/Rio? What were their strengths/ weaknesses? How fussy were they with positioning? What was the tonality like?

I was initially drawn to the Green mountains because of the advertised claims of time coherency which other speakers do not have. What can you say about this? Are there any qualities which are audible with GMA that are lacking in others?