need cable upgrade advice for Dali Mentors

Hi all. I'm upgrading my speakers to a pair of Dali Mentor 6's connected to a Cambridge Audio Azur 551R and would like some advice on cables. I currently own a pair of the Kimber 4PR.

I could ditch the 4PRs and simply invest in nicer single run to each speaker.

Or, I could keep my Kimber 4PR cables and use it with the receiver's bi-amp function (it sends the front L/R signals to the unused surround taps and gives a sort of bi-amping functionality). In this instance I'd want to select a nicer set of cables for the mid/low frequencies.

Budget is up to $600. Probably in a year or so I'll end up with a standalone tube amp anyways (triode corp, primaluna, or rogue).

Any advice would be much appreciated!
I've owned PR's,VS's and TC's. All very fine cables. Recently commented on a previous post about Atlas Equator 2.0 spk. cables. For 5 pounds a meter bare wire, these are steller spk. cables. Very pure copper (6N) and very well constructed. IMO, they will better the PR's by long measure. You can order these thru: and uk. Never had any problems w/either company in the past. For a SONG you can have a wonderfull set of spk. cables. You don't need anything more. Atlas makes a much more expensive cables as well. Best regards, Bill.
I like Transparent, Discovery and Mapleshade with Dali Euphonia and Helicon series speakers
Thanks for your advice, guys. I ended up auditioning a set of Kimber 12TC, Nordost Blue Heaven, and Crimson Audio cables.

Crimsons came out the winner despite the fact that I really wanted the 12TC to come out on top.