"Magnepanmike, can you give a little more insight as to why you feel the MK2 is SS sounding? An example of the system/music and time spent with it perhaps?"
I was using a LS 16 mk1 for 2 years when I purchased a LS25 mk2. I had the both units in my system for about two weeks before I purchased a Ref 2 mk1. (Owned all three units for a month or so before I started selling them off). I felt the LS25 mk2 was very detailed, crisp and clean and fast. Very good pace. Sound seemed to come from the front of the speakers and was very direct, not "layed back". Showed signs of fatique after several hours of listening though. The LS16 mk1 sounded layed back, not as crisp and clean although had lots of bloom. Very easy on the ears.... The LS 16 mk1 was not as crisp. The LS25 mk2 had very little bloom. (I actually like the Pass Labs X-1 better than the LS 25 mk2 as it was more layed back. I ended up with the Ref 2 mk1.....
As you can see I prefer my system to be more layed back than forward. I like the bloom of the 6922 tubes vs. the 6h30's. I have never tried the Calypso, so I really can not comment on that unit, however as you know it gets very high marks..... I'm also not saying that ARC makes the best products out there, it's just that they must be doing something right...... Alot of them are sold, yes, however alot of them are purchased.... It's a matter of economics.
Wish you good luck. (System: ARC 100.2; ARC Ref 2 mk1; ARC CD1 w/DAC5; Maggie 1.6's; sub - cables - power conditioner... yada yada yada)