First, artic fox is white or very light cream in color naturally; therefore, it dyes very evenly and with nice, bright even colors - including black.
Second, artic fox has guard hair that is long fibered and it is not nearly as fuzzy and limp as other fox tail or hair. The guard hair from the artic fos tail runs to about 3 or 4 inches in length.
Third, it is very easy to tie a nice taped wing with artic fox because the underfur is about 60% the length of the guard hair. This allows one to easily cut some artic fox fur from the hide and then strip about 1/2 or a little more of the underfur (which is not real soft and fuzzy like other foxes) from the bunch. This allows one to tie a very nicely taped wing that has more bulk at the tie in point and which gets progressively finer or less bulky as you proceed out to the end of the wing.
Fourth, artic fox is slightly translucent, and the underfur is also somewhat translucent. This allows some light to be gathered and reflected along the wing when fishing. The other foxes do not have this characteristic.
Fifth, artic fox is a bit crinkly at its base and since its underfur is also crinkly, it allows one to tie a nice looking wing that actually has very little bulk, thus making casting easier and letting less air get into the wing during casting, which helps sink the fly faster when fishing.
Sixth, artic fox is not slippery like the other foxes. This allows one to use far fewer thread wraps to tie it in securely. Thus allowing one to have a smaller, sleeker head that helps the fly to swim better.
In short, artic fox is very different than the other foxes.