Looking for SS amp to power KEF Reference 107s: Rowland, Mccormack?

I'm looking for an amplifier to power a completely restored pair of KEF 107s I have in my main system.
My current amp is a Conrad Johnson mf-2250. The pairing sounds "fine", but I don't feel I'm getting the most out of the 107's. They're spec'ed at 90 dB efficiency, and according to the manual can be driven with as little as 50 watts and on up to 300 watts. They present a 4 ohm resistive load to the amp.

The cj is a nice amp (150 watts at 8ohm, no 4ohm rating published ) but I originally bought it to power my Gemme Audio Tantos which were a lot more efficient than the 107s. I feel the CJ / Gemme was a better pairing than the current CJ / KEF. I get the sense that the cj can't get a grip on the 4 10" drivers. The bass can be a little loose on certain recordings, and I feel there's some loss of air and sparkle up top. The t-33 tweeter (ferro-fluid replenished) is not the greatest driver to begin with.

A few amps have piqued my interest for differing reasons, including the Mccormack DNA-2. I used to own and regretfully sold a DNA-0.5, so Im familiar with the DNA...DNA. It would likely provide all the power and current I could ever want for these speakers (possibly overkill), but would command quite a bit of floor space in my living room, displeasing my wife in the process. 

On the other side of the spectrum, I'm interested in the Rowland Model 2. While It does not offer any additional power (150 watts@ 4 ohms) over my CJ , I like what I've read about its ability to control and tighten up bass, and the sense of air and transparency it offers on the high end. The build quality appears beyond reproach, and a quality over quantity approach always appeals to me. While it's less imposing in size than something like the DNA-2, I wonder if it's limited power would be a lateral move from my CJ.

As for listening habits, most dedicated "sessions" are at lower to moderate levels. Jazz ( Paul Desmond,Jim Hall, Metheny, Miles, Bill Evans). R&B ( Jill Scott, Eryka Badu, Marvin Gaye) while my wife is sleeping, so low level resolution is high on my list. Something I've read the Rowland excels at. There are times when we'll "rock out" when cleaning the house . Non critcal sessions when the living room becomes a whole house system (the floor plan is short on square footage, but big in volume, with few walls and cathedral ceilings. Instances where I really push the system are few.

I should add that sometimes, based on recording, employ the use of dual, sealed, subs (uls-15s). Again, open floor plan, this is where bass goes to die.

I'd welcome thoughts on either of these options and any other amp pairings as ithey pertain to the 107s.
I've done some looking into older Threshold and Pass models as well. I'm solidly in the used market, as I'm a value freak.

thanks for any insight.

I had a Rowland 8T for over 15 years Im now using pass 350.8 it has more dynamic range,great stage ,wonderful bass etc.Good luck.