How may wow directories? Shall I use 1HD or 2HDs?

Hello. I have 2 hard disks in my computer (both are quite similar, Seagate 320 SATA2); which is the best thing to do in order to get maximun performance?:

a) have wow in two different directories. One in the mail disk (C:) and other in E:. Run the main toon from C: and the slaves from E:
b) just have one directory in C: and run 5 wow.exe from it.
c) just have one directory in E) and run 5 wow.exe from it.
d) any other option you may suggests.

You can assume that OS is installed on C:

Loading a toon or using my hearhstone takes me a lot of time, and probably if I can improve HD transfer, it will be less painful.

Thanks a lot for your help.

Since you have two very similar drives, keep the OS on C:, and just use 1 WoW folder on the D: drive for all instances of WoW. The C: drive will be frequently accessed by the OS/swapfile, so it'd be better to keep one WoW directory to run all instances of WoW from on the D: drive. That'll mean queues for accessing WoW/data won't compete with OS queues for swap access. The performance improvement may not even be measurable, but it wouldn't be worse to keep WoW on a separate (but equal in performance) drive.

Thank you very much for your answer. I will sure try that.

I agree with putting WoW on a separate drive from Windows. If you aren't satisfied with that, you could try creating 5 copies of your WoW folder and symlink your Cache, Data and I do my Interface as well. I don't play on my main wow folder, just the five copies. I update the main folder with new addons and patches. This made a noticable difference for me.

I do what the above poster does. (apart from symlinking the interface folder which i really need to do in future).

I have my main install for soloing, Then 5 copies of wow with the symlinking as above. This significantly speeded up things.

I only have one HD.