I also preferred the 57's over the 63's and lived with the 57's in a second system for a while. I preferred my Sonus Faber Electa's over the 57's, particularly driven by a tubed amp. So my recommendation would be to try the smaller standmount SF's and maybe use a CJ CAV 50 integrated. You asked for specific experiences so I'll stick to what I've owned and suggest trying Sonus Fabers with CJ tubes.
On the other hand, if imaging is your main priority, there are probably better choices out there than the SF's. But it's hard not to fall for their midrange and purity of tone/timbres.
Good luck
Rooze
On the other hand, if imaging is your main priority, there are probably better choices out there than the SF's. But it's hard not to fall for their midrange and purity of tone/timbres.
Good luck
Rooze