I got the speaker about a week ago. I have been playing it in my Two Rock and an 18 Watt sIII proto and a TMB.
In terms of loudness it sounds a little bit more efficient than a Greenback even though the Sammi is 96.0 dB/W/M and the GB is 97. In terms of tone the Sammi has a fairly complex midrance character. I am still trying to figure it out a bit. Anyway it has a grind to it that I like and the bass and lower mids still stay focused. The highs are rolled off nicely so I am looking forward to checking it out with the 15 watt.
The clean sound is bright but not too bright. The cone seems to break up but in a nice warm way. I am going to break it in a bit with a transformer (being the impatient SOB that I am) and see if/how the tone changes.
For now, here is a clip I bashed out on the day I got the speaker. I am using the first Trinity sIII (now on it's way to a happy customer!) and my 335. Please forgive my Page envy.
Sammi Sound Clip