Lougiants,
You are correct about the price difference, and yes, the cost of the Valhallas is quite expensive. (However, I should point out that the cost of bi-wired AU24 cables is almost double the normal cost, as they actually double the runs, as the cable is so thin that they can not split it like they can the Valhallas.) And I should point out that you are giving the NEW retail price of the cables.
However, most of us here on Audiogon buy our equipment used, and this is especially true of cables, (since they are easy to ship and rarely have any damage or wear and tear on them). Several years ago, when I bought my two pairs of AU 24 speakers cables, (2 meters for each pair), as I wanted to bi-wire them, the total cost was about $1,000. When I upgraded to the Valhallas a little over a year ago, the cost was about $3,000 to buy a 2 meter pair of bi-wired Valhallas. Therefore the cost difference was only $2,000. And when you get up to the performance level that I am at, the extra $2K is not nearly enough to upgrade any one piece of equipment, so the upgrade in sonics that I got from the Valhallas is money well spent, IMHO.
I should state that I have not heard the AU24E cables, but I have heard very good things about them. (In case you're wondering why I went with the Valhallas, it was because I had heard them in my friend's system, who also uses Lamm amps, and because a reviewer I know, also used both Lamm amps as well as EgglestonWorks Andra II speakers, which is my setup exactly.) Therefore, I had two very good references that indicated that there would be a good deal of system synergy using them, (which there is I am glad to say).
My two cents worth anyway.