Opinions on speaker cable upgrade

I've been on an upgrade binge and want to upgrade my Acoustic Zen Satori Shotguns. Amp/preamp are tubed. Speakers are Von Schweikert 4 Jrs. If PAD Venustas were less expensive (and more available used), I'd go for those. I need biwired cable. Detail,and imaging important. I'd prefer hearing from those who are familiar with the AZ Satoris and/or the Venustas. Thanks in advance for all of your input. Budget is $1500 used.