Choosing Integrated Amp For New B&W Speakers

I put down the $4k for the B&W 705 Signature and could not be happier. Listening area is approx. 145 sq ft. Compared to my previous LSA1 , the difference is night and day in most every way. The realism in vocals & instruments , potency in performance, clarity and transparency, taut and nimble bass (yep the 705 Sig handles bass quite admirably) detail retrieval and just a fresh treatment to most all music genres thrown at it.

Now for a new int amp to maintain the overall character of this upgraded 705 series design while accentuating attributes such as timbre and  air between vocals/ instruments , musical realism , fluidity and sounstaging. In other words, an amp to get every last morsel of goodness from the 705 signature speakers. 

My shortlist is for now :

Cambridge Audio Edge A - Super refined , smooth and ever so silky , lacks gravitas at times though.

Krell k-300i - Muscular sound , big presence , does it still provide nuance and lightness when needed or is it all heavy going ?..Some mentions of Krell and B&W being a good match : adding weight and punch to the B&W bottom end, yet how does this amp in other areas. Is it all muscle or does it have finesse and elegance to offer in addition.

Luxman 507uxii - Tonally accurate , alluring presentation , although some concerns expressed about soundstaging. 

Now, the chances of auditioning  all is quite remote.  The ultimate choice will come down to reviews for each product coupled with feedback from those who have some insights to share from experience with any or all of the above amps, paired in this case with B&W speakers. .........thanks to all in advance.