Top Audiophile Ethernet Cables - any comparisons?


I just set up my new streamer with which I stream music from my mac mini to my dac. I use a dedicated network switch which connects the streamer and mac mini directly without going through the rest of my LAN.
I exchanged a standard CAT 7 cable on one leg of the connection with Audioquest's Forest Ethernet cable. There was a small but clearly audible improvement. From the reviews on the Web I conclude that the top cable by Audioquest (Diamond) would give the biggest improvement of all Audioquest Ethernet cables. 

Now my question: Has anyone compared the Audioquest Diamond with any other top cable by another manufacturer, e.g. Purist Audio, Cardas, Chord, ...? I live in Switzerland and have no dealer who can give me several of those cables to try. Thus, before spending a lot of money, I'd like to hear any opinions.

Thanks a lot for any replies!

By the way, I use a network switch that was modified for audiophile purposes (AQVOX). The difference to an off-the-shelf switch is tremendous!
belcantor
@david_ten: Thanks for the most helpful link - haven't found that site yet!

@willemj: Thanks for the link. Despite the theoretical considerations I did hear a difference between the two cables I was trying out. Measurements only help if they measure the relevant things.

@jinjuku: A lot of people (including me) would be grateful if you will share the results of your blind test.
Cables that I've had:

Audioquest Vodka 1 meter $340 ($82.5 / foot)
WireWorld Starlight 3 meter $340 ($27.5 / foot)
Nordost Heimdall II 1 meter at $700 ($233 / foot)
Berktek Hyper 5e    98 meter at $90 ($0.30 / foot)

Differences that anyone could hear: 0
@jinjuku,

Please eloborate on ‘anyone’ and the system details these test were performed.  

Thank you!

Laptop as server <> Cisco SG 200-8<> Cary Audio DMS 500 <> RME UFX <> AKG 701 HP

Laptop as server <> Cisco SG 200-8<> Cary Audio DMS 500 <> RME UFX <> USB to PC for recording of tracks. 

Swapped out the cable between tracks. 

Computer (as server) with Intel Dual Port GBe NIC<>Cisco SG-200<>Computer as client with Intel Dual Port GBe NIC/JRiver<> Emotiva Stealth DC-1 <> AKG 701 HP

Swapped out the cable while PLAYING tracks. No one could tell when the cable was swapped even though the music was never interrupted (continued playing even with the Ethernet cable disconnected).