Recommended integrated amplifier for upgrade

CODA CSIB Integrated 

I can't speak to Audio Science's possible affiliations or commercial biases.  I'll be honest, though - I'm a litle biased against it.  The sheer number of reviews suggest that they are really just lab tests.

I did read the Topping review linked above.  His one paragraph listening test consisted of hooking up 1 speaker.  You may each reach your own conclusion as to the ultimate value of this lab test.

I own a Rogers High Fidelity EFH 200 Mark II Integrated Tube amp & really like it. Very powerful, very well made & sounds excellent top to bottom. It s very dynamic,  w/lots of detail & a dead silent black background. No tube noise even w/ the volume up on efficient speakers. Its hand made by Roger & his staff in MA w/ a full lifetime warranty! It operates in class A mode so it runs hot & needs breathing room but worth it. You can watch several videos on youtube by Roger about his amps, their design, build quality etc. Good luck.

@auronthas, not familiar with your speakers but seems they are 4 Ohm jobs. As such, I would be very wary of the MAC MA5300. Nice amp but not sure its power supply is up to the task with those speakers. It'll drive them OK, I think, but not sure it will really make them sing. I've done serious seat-time with the MAC MA5300 and the Moon 340i that overthemoon mentioned. I'd recommend you check out that amp paired with speakers as similar to yours and/or 4 Ohm nominal load speakers of similar sensitivity to see what you hear. In short, if  you are considering Class A/B amplification for those speakers, you should listen to stuff that has a robust current supply.

I run a MA5200, the predecessor to the 5300 in my office system and it has run all the speakers I've connected to it just fine, including Concertino's and Concerto's from SF.  The Luxman, Accuphase or the McIntosh the OP listed would be great.  Just flip a 3-sided coin and pick one.